Modular mail processing method and control system

ABSTRACT

A modular mail processing method and control system for sorting pieces of incoming, internal, and outgoing mail including a plurality of sorting bins which correspond to either mail stops or zip codes depending on which sort plan is selected. The modular mail processing method and control system permitting mixed pieces of mail of various sizes to be sorted. Additionally, an internal mail envelope, which has address regions consisting of blocks, may be utilized in connection with the modular mail processing method and control system in order to allow accurate detection of handwritten addresses.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application of U.S. patent application Ser. No. 126,137, filed on Sep. 23, 1993, now U.S. Pat. No. 5,363,967, the content of which is relied upon and incorporated by reference herein, which, in turn, is a continuation application of U.S. patent application Ser. No. 07/742,751, filed on Aug. 9, 1991, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a mail processing system; and in particular, to a modular mail processing method and control system for sorting incoming, outgoing, and internal mail.

2. Discussion of the Related Art

Traditionally, mail processing systems are custom systems designed for a particular customer's needs. These systems are typically designed for high volume installations such as those that sort 30,000 to 40,000 pieces of mail per hour. With such large installations, custom designs to process either outgoing mail or internal mail are economically feasible. In these designs, the mail processing machinery and associated control system are fixed designs for the installation and are not easily modified for either future requirements or for the needs of other installations. Such custom designs are not economically practical for smaller installations that process in the range of 20,000 to 100,000 pieces of mail per day. Thus, there exists a demand for a low cost, flexible processing system that can be inexpensively and quickly reconfigured to meet the needs of such low volume installations.

Additionally, corporate and institutional mail rooms, which primarily constitute these smaller installations, typically maintain large staffs for handling the mail that must be processed daily. The type of mail processed by the typical corporate or institutional mail room includes internal mail, which originates within the organization and has a destination also within the organization, incoming mail, which comes into the organization from external sources, and outgoing mail, which originates within the organization and has a destination external to the organization. Moreover, in the typical corporate or institutional mail room, 60% of the daily mail is internal, 35% is incoming, and 5% is outgoing. Therefore, in order to be practical, mail processing systems for these smaller installations should be capable of sorting the organization's internal and incoming mail into bins corresponding to internal mail stops as well as sorting the organization's outgoing mail.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made in view of the above circumstances and has as an object to provide a low cost, flexible, modular mail processing method for sorting internal, incoming, and outgoing mail.

It is another object of the present invention to provide a low cost, flexible, modular mail processing control system for sorting internal, incoming, and outgoing mail.

It is yet another object of the present invention to provide a modular mail processing method and control system capable of reading handwritten addresses on internal office envelopes.

It is still another object of the present invention to provide a modular mail processing method and control system capable of performing real time address correction for improperly addressed pieces of internal, incoming, and outgoing mail.

Additional objects and advantages of the invention will be set forth in part in the description which follows and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve the above and other objects, the present invention provides a method of processing pieces of internal mail received from an internal source in a system including a stacker module having a number of carriers and bins, a plurality of serially connected induction transfer modules, including a feeder module, that are positioned to transport the pieces of internal mail from the feeder module to the stacker module, the method comprising the steps of: (a) monitoring the position of each carrier; (b) pre-selecting an empty carrier; (c) feeding a piece of internal mail from the feeder module to another induction transfer module at a desired time based on the position of the pre-selected carrier; (d) tracking the position of the piece of internal mail through the induction transfer modules; (e) obtaining address information from the piece of internal mail, wherein the address information includes a mail stop; (f) selecting a bin for the piece of internal mail based on the address information, the selected bin corresponding to a mail stop; (g) transferring the piece of internal mail from a last induction transfer module to the pre-selected carrier; and (h) diverting the piece of internal mail from the selected carrier to the selected bin.

The present invention also provides a method of processing pieces of incoming mail received from an external source in a system including a stacker module having a number of carriers and bins, a plurality of serially connected induction transfer modules, including a feeder module, that are positioned to transport the pieces of incoming mail from the feeder module to the stacker module, the method comprising the steps of: (a) monitoring the position of each carrier; (b) pre-selecting an empty carrier; (c) feeding a piece of incoming mail from the feeder module to another induction transfer module at a desired time based on the position of the pre-selected carrier; (d) tracking the position of the piece of incoming mail through the induction transfer modules; (e) obtaining address information from the piece of incoming mail, wherein the address information includes an addressee's name; (f) selecting a bin for the piece of incoming mail based on the address information, the selected bin corresponding to a mail stop; (g) transferring the piece of incoming mail from a last induction transfer module to the pre-selected carrier; and (h) diverting the piece of incoming mail from the selected carrier to the selected bin.

The present invention further provides a modular mail processing control system for controlling the flow of mail through a series of induction transfer modules to a stacker/transport module that includes a number of carriers and bins, the system comprising: feeder means, located in one of the induction transfer modules, for injecting a piece of mail into another induction transfer module at a desired time based on a pre-selected carrier being at a given position, and for identifying the piece of mail; encoder means, located in one of the induction transfer modules, for obtaining address information from the piece of mail and for identifying a bin for the piece of mail, wherein the address information includes a mail stop, and the bins correspond to mail stops; tracking means, located in each of the induction transfer modules, for tracking the position of the piece of mail as it moves through the induction transfer modules, and in response to a position error stopping the series of induction transfer modules, storing the identification of at least the piece of mail involved in the position error and storing the position of the induction transfer modules of the stacker/transport module; inserter means, located in one of the induction transfer modules for inserting the piece of mail into the pre-selected carrier when the pre-selected carrier arrives at a desired location; and means for diverting the piece of mail from the carrier to the identified bin.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification illustrate several embodiments of the invention and, together with the description, serve to explain the objects, advantages, and principles of the invention. In the drawings,

FIG. 1 is a schematic diagram of an induction transfer portion of a mail processing system in accordance with the present invention;

FIG. 2 is a schematic diagram of a stacker/transport module in accordance with the present invention;

FIG. 3 is a schematic diagram of a modular mail processing control system embodying the present invention;

FIG. 4 is a schematic diagram of an embodiment of the modular processing control system software in accordance with the present invention;

FIG. 5 is a logic diagram of the bootstrap processing;

FIG. 6 is a flow diagram of the task scheduler;

FIG. 7 is a flow diagram of the manual feed terminal interface real time software module;

FIG. 8 illustrates the display at the system console during the manual feed process;

FIG. 9 is a simplified state diagram for the system state supervisor;

FIG. 10 is a logic flow diagram of the process performed to enable the system to perform a sort;

FIGS. 11A-11D illustrate the display at the system console during the FIG. 10 process;

FIG. 12 illustrates the display 10 provided at the non real time CPU 275 when displaying the status of the system;

FIG. 13 is a logic flow diagram of the log on screen process shown in FIG. 10;

FIG. 14 is a logic flow diagram of the Enter Operators Processing shown in FIG. 10;

FIG. 15 is a logic flow diagram of the Choose Sort Type process shown in FIG. 10;

FIG. 16 is a logic flow diagram for the Choose Sort Plan processing shown in FIG. 10;

FIG. 17 illustrates a display as the non real time CPU 275 that occurs when an operator selects the reports option shown in FIG. 4;

FIG. 18 illustrates the display at the non real time CPU 275 when the operator selects the administration option;

FIG. 19 illustrates the display at the non real time CPU 275 when the operator selects the maintenance option;

FIG. 20 is a schematic diagram of the real time statistics maintained by the FIG. 3 controller;

FIGS. 21A-21C provide an example of the type of information maintained by the non real time CPU 275; and

FIG. 22 is a graphic representation of an internal mail envelope according to one embodiment of the present invention; and

FIG. 23 is a graphic representation of an internal mail envelope according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.

As used herein, the term "piece(s) of mail" is intended to broadly include pieces of internal, incoming, and outgoing mail. It will be understood that the mechanics of sorting these different types of mail are similar with the general exception that different portions of the address listed on the pieces of mail are used to sort the mail. For example, the zip code, state, and city portions of an address are typically used to sort outgoing mail, while an addressee's name and mail stop portions of an address are used to sort incoming and internal mail.

The majority of pieces of internal mail typically consist of interoffice flats envelopes 13×10 inches and less than one inch thick. These interoffice envelopes include a plurality of lines for writing a destination address. Users of the envelopes normally cross out a previously written address and handwrite the destination address on the next line. The envelope is then delivered to the first address not crossed out.

To facilitate sorting of internal mail, uniquely designed interoffice mail envelopes may be distributed for use in sending internal mail. Two examples of such interoffice mail envelopes 400 and 500 are shown in FIGS. 22 and 23.

Envelope 400, shown in FIG. 22, is similar to conventional interoffice mail envelopes with the exception that the region 410 designated for writing the destination mail stop is formed of a plurality of blocks 415. Persons using envelope 400 preferably write one character of the destination mail stop per block 415. Envelope 400 further includes an address region 420 for writing an addressee's name.

Envelope 500, shown in FIG. 23, differs from that shown in FIG. 22 in that the region 520 designated for writing the addressee's name is also formed of a plurality of blocks 525. Persons using envelope 500 preferably write one character of the addressee's name per block 525. Like envelope 400, envelope 500 further includes an address region 510 including a plurality of blocks 515 for writing a mail stop.

By providing the blocks 415, 515, and 525, the mail sorter can more readily distinguish the handwritten characters representing the destination name and mail stop. Thus, by using envelopes encompassing the concepts of those shown in FIGS. 22 and 23, the mail sorter may sort internal mail more accurately and with less human intervention.

Envelopes 400 and 500 offer the additional advantage that users may cross out a previously written address and handwrite the destination address on the next line in the same manner as conventionally performed. Thus, it is not necessary that users utilize preprinted address labels.

Envelopes 400 and 500 additionally may include unique marks 430 and 530, respectively, to identify the envelope as an internal mail envelope. Upon reading one of these marks 430 and 530, the mail processing system of the present invention searches for the first mail stop that has not been crossed out, and performs character recognition on the handwritten characters of the mail stop. Subsequently, the mail processing system of the present invention performs a context correlation to verify that the mail stop is a valid mail stop. Additionally, the mail processing system may search for the first addressee name that has not been crossed out, and perform character recognition on the handwritten characters of the name. Again, the mail processing system performs a context correlation to verify that the written name is a valid name. By performing correlations on both the mail stop and the addressee's name, the mail processing system may sort the piece of internal mail more accurately.

Additionally, envelopes 400 and 500 may include address regions 440 and 540, respectively, for writing the plant or office of the addressee. These address regions 440 and 540 may also be provided with a plurality of boxes for processing the information written therein in the same manner as described above with respect to the names and mail stops.

Conventional mail processing systems are designed for sorting external or outgoing mail. Such mail processing systems sort outgoing mail by correlating external addresses (i.e., the street, city, state, and zip code of the address). Therefore, conventional mail processing systems have not correlated addressee names or mail stops in sorting mail. Therefore, the present invention has been designed to include a database in which the names and mail stops of personnel to permit sorting of incoming and internal mail by correlation of addressee names and mail stops. By maintaining an updated database of names and mail stops, an organization employing the present invention, may ensure reliable mail delivery to personnel who frequently relocate or leave the organization.

Incoming mail typically includes pieces of mail that vary considerably in size. Thus, to sort incoming mail, a mail processing system must be capable of sorting pieces of various sizes. The mail processing system of the present invention has this capacity as will be further described below.

In sorting incoming mail, the mail processing system of the present invention, searches the address of a piece of incoming mail for a name that corresponds to a name stored in the database. Upon recognizing the addressee's name, the system identifies the present mail stop of the addressee, and sorts the piece of incoming mail to a bin corresponding to the identified mail stop.

In the event that the addressee's name is identified, but the address is incorrect, as would be the case of an employee who has moved to a different location, the present invention prepares a forwarding label including the proper address of the addressee and sorts the piece of mail to an appropriate bin for forwarding mail.

When an employee's address changes, the database may be updated to include the new address without erasing the old address. The old address may be then be used to ensure proper correlation and identification of the employee.

When used to sort outgoing mail, the modular mail processing system of the present invention preferably assigns zip codes to its sorting bins and sorts the outgoing mail based on zip codes when an outgoing mail sort plan is selected. On the other hand, when an incoming or internal sort plan is selected, the modular mail processing system preferably assigns mail stops to its sorting bins and sorts the incoming or internal mail based on mail stops. Thus, by selecting the appropriate sort plan, one may properly sort incoming, internal, or external mail.

A detailed description of the mail processing system of the present invention will now be described.

FIG. 1 is a schematic diagram of an induction transfer portion of a mail processing system in accordance with the present invention. In FIG. 1, reference numeral 20 identifies induction transport modules. As shown in FIG. 1, the induction transport modules are connected in series to form an induction transfer line 25 in FIG. 1, reference numeral 30 identifies an automatic feeder induction transfer module, reference numeral 35 identifies a manual feeder induction transport module, reference numeral 40 identifies an encoder induction transport module. The encoder induction transport module 40 feeds pieces of mail to an inserter induction transport module 45 which inserts the pieces of mail into a selected carrier 50 of a stacker/transport module 55.

FIG. 2 is a schematic diagram of a stacker/transport module in accordance with the present invention. The stacker/transport module 55 shown in FIG. 2 includes a number of bins 60. Referring to FIG. 1, an encoder 65 provides pulses to a control system (FIG. 3) identifying the location of carriers such as the carrier 50 within the stacker/transport module 55. The control system shown in FIG. 3 monitors the position of each carrier based on a number of pulses generated after the carrier is sent by a carrier number 1 sensor as shown in FIG. 2. Also shown in FIG. 2 is a chain stretch sensor 75. This sensor senses the amount of flex in a chain 80. A drive sprocket (not shown) can then be adjusted to take up the slack in the chain 80.

Referring to FIG. 2, when a carrier 85 reaches a selected bin 90, a diverter 95 is activated to move a rake 100 so as to engage the carrier 85; thus, deflecting the mail in the carrier 85 into the selected bin 90.

The control system shown in FIG. 3 controls the modular mail processing system shown in FIG. 1 so that a piece of mail injected into the induction transfer line by either the automatic feeder 30 or the manual feeder 35 reaches the selected carrier 50 when the selected carrier 50 is positioned to receive a piece a mail from the inserter induction transfer module 45. In a preferred embodiment of the present invention, the induction transfer line 25 operates at approximately 75 inches per second. The controller shown in FIG. 3 maintains the status of each carrier based on when a carrier is fed with a piece of mail and when a piece of mail is diverted out of a carrier. The FIG. 3 controller therefore selects an empty carrier based on this maintained status. The carrier empty sensor 110 and the carrier full sensors are used by the FIG. 3 controller to detect errors when the maintained status differs from the detected status of a carrier. The control system shown in FIG. 3 determines the distance of the empty carrier 105 from an arbitrary starting line 115 shown FIG. 2. The position of the starting line 115 is selected so that a carrier will arrive at the location adjacent the inserter module 45 in a position to receive a piece of mail from the inserter module 45 given a nominal rate of flow of a piece of mail through the induction transfer line 25. Thus, for example if the induction transfer line 25 is operating at the same rate as the carrier (75 inches per second) and the length of the induction transfer line from, for example, the output of the auto feeder 30 to the output of the inserter module 45 is 25 feet, then the starting line 115 is positioned 25 feet from the point at which the selected carrier 50 arrives at a position with respect to the inserter module 45 to receive mail from the insert module 45. In such a case, when an empty carrier 105 reaches the starting line 115, then the control system shown in FIG. 3 would feed a piece of mail, via the auto feeder 30, to the induction transfer line 25. There is, of course, a different starting line for the manual feeder 35. Since the manual feeder 35 is closer to the desired position of the empty tray 105 adjacent the inserter module 45, the starting line for the manual feeder 35 would be closer to the inserter 45 than the starting line 115. Functionally, when an empty carrier reaches a starting line, the controller shown in FIG. 3 checks to see if there is a piece of mail to be fed by either the manual feeder 35 or the auto feeder 30. If there is a piece of mail to be fed into the induction transfer line 25, the FIG. 3 control system starts the appropriate servo motor at either the auto feeder 30 or the manual feeder 35. For example, if an empty carrier is at the starting line 115, and the auto feeder 30 has a piece of mail to insert into the induction transfer line 25, the FIG. 3 controller starts the servo motor 120 to feed a piece of mail into the induction transfer line 25. When a piece of mail is fed into the induction transfer line 25, the FIG. 3 controller stores an identification of the piece of mail together with the thickness of the piece of mail. FIG. 3 controller may also store the weight of the piece of mail with the identification of the piece of mail. A series of sensors 125-152 are located amongst the induction transport modules 20. The sensors detect the presence of a piece of mail, and comprise, for example, through beam type sensors. Each piece of mail inserted into the induction transfer line 25 is individually identified by the FIG. 3 controller and tracked through the induction line 25. For example, when the auto feeder 30 is instructed by the FIG. 3 controller to insert a piece of mail, the leading edge of the piece of mail is detected by the sensor 125. If the piece of mail is traveling normally, then the FIG. 3 controller detects the trailing edge of the piece of mail passing the sensor 125. If the sensor 125 detects another piece of mail before the trailing edge of the current piece of mail leaves sensor 127, then a position error or jam situation exists.

As a preferred alternative, when sensor 125 detects the piece of mail, FIG. 3 controller calculates an arrival time at inserter module 45. If the piece of mail is going to arrive too late, then there is a jam. To perform this function, FIG. 3 controller calculates actual position and desired position and compares the two. If the difference exceeds a predefined threshold, a jam is deemed to exist. In the present invention, the predefined threshold may be adjusted to account for the types of mail the user typically sorts. Preferably, this predefined threshold is set at ±3 inches.

When a jam occurs, the FIG. 3 controller stores the identification of the current piece of mail as well as the other piece of mail and begins to shut down the induction transport modules 25 and the stacker/transport module 55. The FIG. 3 controller stops feeding mail to the transfer line 25. The FIG. 3 controller then stops all motors, and determines in which module the position error occurred. The motors at this point are slowing down towards a stop. The FIG. 3 controller informs the operator of the jam and its location via the system console. The operator then removes the pieces of mail that need to be removed, and presses a system start button. In response to the system start button being pressed, the FIG. 3 controller turns all of the motors back on at a slow speed and waits until all of the mail is out of the induction transfer line 25 and into the appropriate carriers. At this point, the FIG. 3 controller turns all of the motors onto their normal speed and begins feeding mail normally.

The portion of the induction transfer line between the sensors 127 and 129 is an optional catch-up section 155. In this section, the FIG. 3 controller can adjust the position of the piece of mail based on the amount of movement that the selected carrier has undergone. In other words, the piece of mail in the catch-up section 155 has a desired position and an actual position with respect to the position of the carrier determined based on the output of encoder 65. The FIG. 3 controller can either accelerate or decelerate the piece of mail so that its position coincides with the desired position for the piece of mail. Referring to FIG. 1, when a piece of mail reaches the sensor 127, the FIG. 3 controller determines if a correction is necessary, and if so, how much. Once the trailing edge of the piece of mail is detected by the sensor 127, the FIG. 3 controller actuates a first catch-up servo motor 160. The movement of the piece of mail is thus accelerated or decelerated so that its position coincides with a desired position based on the position of the selected carrier within the stacker/transport module 55. When the leading edge of the piece of mail reaches the sensor 129, the position adjustment stops, and the piece of mail continues to move along the induction transfer line at its nominal rate (e.g., 75 inches per second). The induction transfer line 25 is driven at its nominal rate by three AC synchronous motors 165, 170 and 175 as shown in FIG. 1. Although the present invention is described using three AC synchronous motors, it will be apparent to those of ordinary skill that more or less AC synchronous motors may be utilized depending, in part, upon the number of modules used in the system.

While a piece of mail is between adjacent sensors such as 127 and 129, the FIG. 3 controller monitors for position errors (jams) as described with respect to sensors 125 and 127. Thus, adjacent sensor such as 125 and 127, and 127 and 129 may function as sensor pairs that enable the FIG. 3 controller to track the position of the piece of mail through the induction transfer line 25 and to detect position errors in the induction transfer modules 20.

Again, an alternative method of determining position errors exists wherein the FIG. 3 controller compares actual arrival times with target arrival times and determines that positioning errors exist when the difference exceeds a predefined threshold.

As shown in FIG. 1, an encoder 180 is coupled to the induction transfer line 25. The FIG. 3 controller uses the output of the encoder 180 to determine the position of mail in the induction transfer line 25, or in other words, the position of the induction transfer modules 20. Thus, in the event of a position error detected, as noted above, the FIG. 3 controller determines the position of the induction transfer modules 20. Upon detecting a position error the FIG. 3 controller also determines and stores the position for the stacker/transport module based on the position indicated by the encoder 65. Thus, in the event of a position error the FIG. 3 controller stores the identification of the piece of mail involved in the position together with the position of the induction transport modules 20 and the stacker/transport modules 55. This enables the FIG. 3 controller to stop normal processing of the mail upon detecting a position error, and restart processing of the mail with the induction transport modules 20 and stacker/transport module 55 at their respective positions that existed at the time that the position error was detected.

As shown in FIG. 1, mail pieces can also be injected into the induction transfer line 25 by a manual feeder 35. The manual feeder 35 includes a terminal 185, a cleated belt feed section 190 and a catch-up section 195. The catch-up section 195 includes a servo motor 200 together and with sensor 205 and 135 function in the same manner as the catch-up section 155. The operation of the manual feeder terminal 185 is described in detail below. Functionally, when an operator places a piece of mail in the cleated belt section 190, the FIG. 3 controller determines that the mail is present and determines its thickness. FIG. 3 controller may further determine the weight of the pieces of mail. This information together with an identification of the piece of mail is stored. When the FIG. 3 controller identifies an empty carrier 105 at the starting line for the manual feeder, as noted above, the FIG. 3 controller starts a servo motor 210 that causes the piece of mail to be pushed into the catch-up section 195.

As shown in FIG. 1, the encoder induction transport module includes a number of optional elements. Basically, the encoder induction transport module functions to read address information from the piece of mail and, together with the FIG. 3 controller to identify a bin 90 in the stacker/transport module 55 for the piece of mail. The address information can be detected from the piece of mail by either an optical character reader (OCR) 215 or a bar code reader (BCR) 220. There is, of course, no reason why both of these elements cannot be used in a system. This obviously would increase the cost, but enhance the flexibility of its system. The encoder induction transport module 40 can also include labeler 225, a bar code printer 230 and a verify bar code reading 235. The labeler 225 can be controlled by the FIG. 3 system to print the labels on outgoing mail. The labeler 225 can also be used for address correction. For example, if the OCR 215 reads address information and this address information is incorrect because the destination has been changed, a new label can be printed and applied to the piece of mail by the labeler 225. In addition, pieces of mail traveling through the system can have a bar code printed thereon for future sorting, either at another location or internally. The FIG. 3 control system includes a data base of addresses. This data base can be used to verify the address information read by either the bar code reader 220 or the optical character reader 215. If the destination address has been changed, then as mentioned, the labeler can apply a new label to the piece of mail. In addition, when the bar code reader 220 or the optical character reader 215 reads the address information from the piece of mail, the FIG. 3 controller identifies a bin 60 within the stacker/transport module 55 and stores this with the identification of the piece of mail. Thus, when the piece of mail reaches the selected carrier 50, the stacker/transport module moves the selected carrier 50 while the FIG. 3 system monitors the location of the carriers. When the selected carrier 50 arrives at the appropriate bin 60, the FIG. 3 control system activates the diverter 95 which causes a rake 100 to push the piece of mail out of the selected carrier and into the selected bin 90 as shown in FIG. 2. After the piece of mail leaves the encoder induction transport module, it enters the insert induction transport module 45. The inserter induction transport module functions to change the orientation of the piece of mail from vertical to horizontal for placement into the selected carrier 50. In addition, the inserter induction transport module 45 performs a catch-up function in catch-up section 240. The sensor pair 150 and 152 define the beginning and end of the catch-up section 240. It is not necessary to utilize each of the catch-up sections 155, 195 and 240. In fact, depending upon the type of mail flowing through the induction transport modules 20, it may not be necessary to have any of the catch-up sections. Basically, the catch-up sections 155, 195 and 240 function to adjust the position of the piece of mail which position may have been changed due to slippage of the belts within the induction transfer line 25. Such slippage could occur, by, for example, a thick piece of mail (e.g., 11/4 inches) encountering one or more of a series of dancer pulleys 245 shown throughout the induction transfer line 25. The structure of these pulleys is described in copending U.S. patent application entitled Induction Subsystem For Mail Sorting System by Stanley K. Wakamiya et al., filed Aug. 9, 1991, which is hereby incorporated by reference.

Because the FIG. 3 control system monitors the thickness of each piece of mail fed by the auto feeder 30 and manual feeder 35, it is possible to keep track of the total thickness of mail entered each of the bins 60. Thus, the FIG. 3 system maintains the height or total thickness of the mail in each bin 60. It is not necessary for the FIG. 3 control system to monitor the total thickness in this manner. Instead a sensor could be used to determine when a bin is full. When a bin 60 become 3/4 full, the FIG. 3 system flashes a warning light 250 that is associated with the 3/4 full bin 60. When the bin becomes full, the FIG. 3 system issues a warning by, for example, maintaining the warning light on all of the time; and also maintains any piece of mail destined for that bin in its carrier. In other words, any mail destined for a full bin stays in its selected carrier and circulates through the stacker/transport module 55 until its destination bin is emptied. To empty a bin, an operator pushes a bin button 255 to alert the FIG. 3 control system that the bin is being removed. The FIG. 3 control system also monitors a bin present sensor 260b to determine if there is a bin at a desired location. This is useful if, for example, an operator removes a bin without depressing the bin button 255. In addition, in some embodiments of the present invention when the FIG. 3 control system detects that a bin is full, the control system can activate a next bin actuator 265. This actuator moves the full bin out of its location and inserts an empty bin in its place. The stacker/transport module 55 moves the carriers 85 through the stacker/transport module 55 and past the inserter induction transport module 45 at the same rate that the induction transfer line 25 moves. This rate is variable and in one embodiment of the present invention corresponds to 75 inches per second. The rate is variable via operator control, and also in accordance with the state of the system. For example, if the system is recovering from an error then it moves at a much slower rate.

Since the FIG. 3 control system reads the address information from each piece of mail, identifies each piece of mail as it is fed into the induction transfer line 25, and selects an appropriate bin for the piece of mail, it uses this information to maintain on line statistics concerning the mail flowing the system. These statistics can include, for example, the number of pieces of mail sorted to each bin, the number of pieces of mail to each address (e.g., mail stop) or groups of addresses, the number of pieces of mail that were incorrectly read (e.g., the address information read by the bar code reader 225 or optical character reader 215 was not verifiable by the FIG. 3 control system).

The FIG. 3 system includes a set of sort plans. Each sort plan identifies which addresses should be placed in which bin 60 of the stacker/transport module. The operator can select, as discussed below, which sort plan is to be used on a particular sort run. Thus, when the encoder induction transport module obtains the address information from the piece of mail, the FIG. 3 control system searches the selected sort plan for the appropriate bin for the piece of mail placed in.

FIG. 3 is a schematic diagram of a modular mail processing control system embodying the present invention. The FIG. 3 control system includes two computers, a real time CPU 270 and a non real time CPU 275 that is connected to the real time CPU via an Ethernet link 280. The real time CPU controls the mail processing system via a VME bus 285. A serial port controller 290 interfaces a variety of devices with the real time CPU 270 over the VME bus 285. The serial controller 290 communicates with the variety of devices over a communication link identified in FIG. 3 as being an RS-232 connection. This is only one example and the communication can be of any other convenient type. As shown in FIG. 3, the serial controller controls communications between the real time CPU 270 and the bar code reader 220, the OCR 215, the labeler 225, the bar code printer 230, the verify bar code reader 235, a manual feeder scale 300 that is located in the manual feeder 35, and a manual feed terminal 185. The communication through the serial controller 290 is bi-directional for the labeler 225, bar code printer 230 and the manual feed terminal 185. The serial controller 290 interrupts the real time CPU 270 when one of the devices needs to communicate with the real time CPU 270. On being interrupted by the serial controller 290, the real time CPU 270 determines the source of the interrupt (e.g., manual feed terminal) reviews the data received from the device and generates either a message to internal real time CPU software and/or an output to the device. The internal messages are described in more detail below. An interrupt input circuit 305 collects interrupts from various sensors in the system (e.g., carrier empty sensor, the sensors 125-152), the control panel 310 and the servo motors. The interrupt input circuit 305 interrupts the real time CPU 270. The interrupt processing within the real time CPU 270 identifies the source of the interrupt, generates a message to internal real time software and/or an output to respond to the interrupt. All interrupts in the system are generated in a response to a physical event. For example, if an operator presses a system start button on the control panel 310, the interrupting input circuit 305 interrupts the real time CPU 270. Interrupt processing within the real time CPU 270 recognizes that the source of the interrupt is the system control panel and identifies that the system start button has been pressed. In response, the real time CPU generates a message for internal software such as the following.

MSG₋₋ SYS₋₋ START that is sent to a system state supervisor.

The following table summarizes the interrupts generated by the interrupt input circuit.

                  TABLE 1                                                          ______________________________________                                         Interrupt Designation                                                                           Description                                                   ______________________________________                                         ESTOP            Any of the various emergency                                                   stop buttons within the                                                        system is pushed                                              InserterEntering Input from sensor 150                                         InserterLeaving  Input from sensor 152                                         AF CatchUpEnter  Input from sensor 125                                         AF CatchUpEnter  Input from sensor 127                                         MF CatchUpEnter  Input from sensor 205                                         CarrierEmpty     Input from carrier empty                                                       sensor 110                                                    CarrierFull      Input from carrier full                                                        sensor 111                                                    CNTL Panel.sub.-- Sys Stop                                                                      Control Panel 310 system                                                       stop button                                                   HandAwayMF       Output from safety sensor                                                      315 in the manual feeder 35                                   ChainStretch     Output of chain stretch                                                        sensor 75                                                     CNTL Panel.sub.-- SysStart                                                                      System start button at                                                         control panel 310 pushed                                      MF MailPresent   Mail is present in the manual                                                  feeder 35                                                     MLICR MailPresent                                                                               Output of sensor 135                                          MF OverSizedLetter                                                                              Output from the pleated belt                                                   beat section 190 of the                                                        manual feeder 35                                              Insert Jam Switch                                                                               Input from the inserter                                                        induction transport module 45                                 Carrier 1        Input from carrier 1                                                           sensor 70                                                     AF MailPresent   Output from a sing 320 in the                                                  auto feeder 30                                                MF TwistEnter    Output from sensor 205                                        MF TwistLeave    Output from sensor 135                                        MF MergeSuccess  Output of sensor 137                                          MF InductionJam 1                                                                               Output of sensors in the                                                       induction transfer line 25                                    MF InductionJam 2                                                                               Output of sensors in the                                                       induction transfer line 25                                    MF InductionJam 3                                                                               Output of sensors in the                                                       induction transfer line 25                                    MF InductionJam 4                                                                               Output of sensors in the                                                       induction transfer line 25                                    MF InductionJam 5                                                                               Output of sensors in the                                                       induction transfer line 25                                    MLICR Jam1                                                                     MLICR Jam 2                                                                    Inserter Jam1                                                                  Insert Jam2                                                                    ______________________________________                                    

Each servo motor generates an interrupt when it acknowledges a command sent from the real time CPU 270. In addition, the real time CPU 270 is interrupted whenever a message is received over the Ethernet link 280. The scale 300 shown in FIG. 1 generates an interrupt when a piece of mail is placed on the cleat belt feed section 190. In addition, a counter/timer 325 generates interrupts for the real time CPU 270 whenever, for example, a counter finishes counting and/or a timer elapses. For example, the output of the encoder 65 in the stacker/transport module 55 is counted by a down counter. When the counter, for example, counts down to 0, an interrupt is generated to indicate that a particular carrier has reached a reference station. The counter is reloaded with the appropriate count so that an interrupt is generated when the next carrier arrives at the reference position. This technique permits variable spacing between the carriers.

As shown in FIG. 3, A to D converters 330 provide digital output of the scale 300 to the real time CPU 270. In FIG. 3, reference numeral 335 designates a PAMUX I/O Bus controller. An embodiment of the present invention uses a XYCOM VME Bus PAMUX I/O type bus controller. This controller interfaces the sensors and actuators for the stacker/transport module 55, the lights and alarm indicators on the control panel 310 and the AC synchronous motors such as 165, 170 and 175 shown in FIG. 1. This controller also interfaces the real time CPU 270 with each of the servo motors so as to control the starting and stopping of the servo motors. Referring to FIG. 2, 3 bin modules in the stacker/transport module are illustrated. In each module, there is a diverter 95, warning light 250, bin present sensor 260, a bin button 255 and an optional next bin actuator 265 for each bin location. For the 27 bin stacker/transport module 55 shown in FIG. 2, these sensors and actuators require 135 input output lines. Thus necessitating a bus controller such as the PAMUX I/O bus controller 325. As shown in FIG. 3, the sensors and actuators as discussed above are isolated from the PAMUX I/O Bus Controller 335 by isolation modular boards 340.

FIG. 4 is a schematic diagram of an embodiment of the modular processing control system software in accordance with the present invention. The modular mail processing control software is structured, as shown in FIG. 4 into non real time software and real time software. The non real time software is associated with the system console associated with the non real time CPU 275. As schematically illustrated in FIG. 4, interrupt service routines (ISR) interface the real time software with the actual induction transport modules 20 and stacker/transport module 55. As mentioned above, each physical event in the induction transport modules 20 causes an interrupt. An interrupt service routine recognizes the source of the interrupt, issues a response to the source, and if needed generates a message to one of the modules of the real time software shown in FIG. 4. The message is passed amongst the real time software modules shown in FIG. 4 and the interrupt service routines and over the Ethernet 280s is in accordance with the known TCP/IP communication protocol. On powering up both the real time CPU275, the non real time CPU 275 enters a server listen mode, and waits for the real time 270 to issue a connect message. Upon receipt of the connect message, the non real time CPU 275 issues an accept message to establish a communication link over the Ethernet 280. The non real time CPU 275 begins the system console software as described in more detail below.

After establishing the session with the non real time CPU 275, the real time CPU 270 initializes each of the supervisor tasks shown in FIG. 4. This is accomplished by, and is explained in more detail below, placing a message MSG₋₋ INIT in a message queue for each of these supervisors. The system task schedule is then started. This processing is schematically illustrated in FIG. 5 which represents the bootstrap processing performed in the real time CPU 270.

FIG. 6 is a flow diagram of the task scheduler. The task scheduler is a non-preemptive multi-tasking kernel which passes messages between supervisors and tasks shown in layer 2 of FIG. 4 and accepts messages from interrupt service routines shown in layer 1 of FIG. 4. These messages are passed through a series of message queues; each queue having a priority. Within each priority, the message queue functions as a first in, first out queue. As shown in FIG. 6, the task scheduler handles all of the messages in the current priority before continuing to the next priority.

FIG. 7 is a flow diagram of the manual feed terminal interface real time software module. In step SI, it is determined whether or not the current sort is an automatic sort or one which requires the operator of the manual feeder 35 to enter a mail stop. If it is an automatic mail sort, processing proceeds to step S6. In this step, a message is sent to the manual feed supervisor which then sends a message to the carrier scheduler to feed the piece of mail. The carrier scheduler will then place a message in the message queue for the interrupt service routines to activate the cleated belt servomotor 210 to begin feeding the piece of mail into the induction transfer line 25 shown in FIG. 1. Referring to FIG. 7, if mail stops should be entered by the operator of the manual feeder 35, the system requests that the operator enter a mail stop as shown in the screen illustrated in FIG. 8. If a mail stop is entered, processing proceeds to step S6 as described above. If a mail stop has not been entered, the processing proceeds to step S3 shown in FIG. 7. Referring to FIG. 8, the operator is prompted to enter a name in step S3 of FIG. 7. The names that match are then displayed by step S4 shown in FIG. 7. The operator chooses one of the names by entering the number associated with the desired name. If a name is chosen in step S5 of FIG. 7, then processing continues to step S6 as discussed above. Otherwise, the operator is requested to enter a name again in step 53 of FIG. 7.

The following describes the structure and operation of the layer 2 supervisors and tasks shown in FIG. 4; that is, the Manual Feed Supervisor, the Auto Feed Supervisor, the Read/Print (i.e., encoder) Supervisor, the Inserter Supervisor, the Stacker/Transport Supervisor, the Error/Jam Recovery Supervisor, the Carrier Scheduler and the System State Supervisor. Referring the FIGS. 1 and 4, the Manual Feed Supervisor controls the operation of the manual feeder 35 as schematically represented by the boxed portion of the system shown in FIG. 1. The auto feed supervisor controls the operation of the auto feeder 30 and portion of the induction transport modules 20 as schematically illustrated by the box shown in FIG. 1. The read/print (encoder) supervisor controls the operation of the read/print (encoder) induction transport module 40 as schematically illustrated by the box shown in FIG. 1. The inserter supervisor controls the operation of the inserter module 45 as schematically illustrated by the box shown in FIG. 1. The stacker/transport supervisor controls the operation of the stacker/transport module 55 shown in FIGS. 1 and 2.

In the following, each of the supervisors and tasks is discussed with respect to its Moore machine state table which are to be read and together with the message data dictionary and Appendix A. In addition, Appendix A identifies each message used within the software shown in FIG. 4. The message name is shown in capitals and the parameter, if any is shown in lower case underneath the message name. In the Description portion of Appendix A names having a prefix "isr" identify interrupt service routines for example, referring to the description associated with the message MSG₋₋ ESTOP in Section 1.1 of Appendix A, the source of this message is the interrupt service routine "isrESTOP." Thus, the source of the input message MSG₋₋ ESTOP is the interrupt service routine "isrESTOP". The message is triggered by any one of the emergency stop (E-Stop) buttons being pressed on any one of the induction transfer modules 20 or the stacker/transport module 55. Where the parameter associated with the message MSG₋₋ ESTOP is a boolean parameter that is true if the button is pressed and false if the button is not pressed or reset.

FIG. 9 is a simplified state diagram for the system state supervisor. Appendix B is the Moore machine state table for the system state supervisor. This state table is organized in the same way as all of the remaining state tables. There are four columns in each state table. The first identifies the present state, the second identifies the message input to that state, the third column identifies the next state, and the fourth column identifies the message output by the present state. The manual feed supervisor comprises two state tables. Appendix C is the state table for the manual feeder terminal 185 and cleat belt feed section 190 of the manual feeder induction transport module 35. Appendix D is the state table for the catch space up section 195 of the manual feeder induction transport module 35. The auto feed supervisor comprises three state tables. The first shown in Appendix E shows the auto feeder singulator 320. The second presented in Appendix F controls the actual catch up or position adjustment of a piece of mail within the auto feeder catch up section 155. The last state diagram for the auto feed supervisor is presented in Appendix G which controls the calculation of the amount of adjustment to the piece of mail that is to be made by the catch up section 155. The state machine shown in Appendix G also controls the general operational state of the catch up section 155 including its rev up, ramp down and stopping on a position error or jam detection as shown in Appendix G. The amount of position adjustment to be made by the catch up section 155 is based upon the difference between the desired position of the carriers within the stacker/transport module 55 and the actual position as determined by encoder 65. The difference between these two positions identifies the amount of position adjustment to be made by the catch up section 155.

The read/print (Encoder) supervisor state diagram is presented in Appendix H. The state diagram presented in Appendix H controls only the OCRN 215 shown in FIG. 1.

The inserter supervisor state machine actually comprises two state machines. Appendix K presents the state machine for the catch up section 240. This state machine controls when the position adjustment to be affected by the inserter induction transport module 45 should begin and end. The state machine shown in Appendix I is similar to that discussed with respect to the auto feed catchup date machine presented in Appendix F. That is, the Inserter supervisor state machine presented Appendix J controls the general operational state of the inserter and calculates the amount of position adjustment to be made by the inserter in the same manner as described with respect to the auto feed catch up section 155.

The Stacker/Transport Supervisor state machine is presented in Appendix K, and the Error/Jam recovery supervisor is presented in Appendix L.

The carrier scheduler is not a state machine and therefore Appendix M presents the pseudocode for the carrier scheduler. Both the manual feed supervisor and the auto feed supervisor send messages to the carrier scheduler via the task scheduler and associated message queues. These messages identify which of the feeders, the automatic feeder induction transport module 30 or the manual feeder induction transport module 35 has sent the request to feed a piece of mail.

In an embodiment of the present invention, the non real time software is implemented using Microsoft® Windows. As shown in FIG. 4, on power up after the non real time CPU 275 and the real time CPU 270 establish a connection as described above, the non real time CPU 275 such as shown above the dotted line portion of FIG. 4. Basically, the non real time software has log on functions, sorting functions and system functions. FIG. 10 is a logic flow diagram of the process performed to enable the system to perform a sort. FIGS. 11A-11D illustrate the screens displayed by the non real time CPU 275 during the process illustrated in FIG. 10. FIG. 12 illustrates the display provided at the non real time CPU 275 when displaying the status of the system.

FIG. 13 is a logic flow diagram of the log on screen process shown in FIG. 10. In FIG. 13, the first step is to display the log on screen such as shown in FIG. 11A. At this point, the system waits for the operator to enter a password and a user name. The system then checks to see if the password matches the appropriate password for the user name. If not, the log on screen is again displayed. If the password and user name match, the sort and system menus shown in FIG. 4 are enabled and processing continues as shown in FIG. 10. As is common with programs written with Windows, if the operator selects either the OK area or the Cancel area, processing continues to the next process shown in FIG. 10.

FIG. 14 is a logic flow diagram of the Enter Operators Processing shown in FIG. 10. The first step is to display the inter operators screen. At this point, the system waits for the operator to enter at least one name. As discussed with respect to FIG. 11A, the operator can select either the OK or Cancel area and leave the operation. If the operator enters a name, the name is stored and processing continues as shown in FIG. 10.

FIG. 15 is a logic flow diagram of the Choose Sort Type process shown in FIG. 10. Referring the FIG. 11C and to FIG. 15, the sort mode screen is displayed first. The system then waits for the operator to choose one of the selections. If the operator chooses cancel, the processing continues as shown in FIG. 10 otherwise the selection is stored and processing continues as shown in FIG. 10.

FIG. 16 is a logic flow diagram for the Choose Sort Plan processing shown in FIG. 10. Referring the FIG. 16 and FIG. 11D the Choose Sort Plan Screen is first displayed. Next, the sort plans associated with the sort mode are displayed and the system waits for the operator to select a sort plan. If no sort plan is selected, the system start button on the control panel shown in FIG. 3 is nonfunctional. When the operator selects a sort plan, the selected sort plan is then sent to the real time CPU 270, and processing continues as shown in FIG. 10. More particularly, the status such as shown in FIG. 12 is displayed as the non real time CPU 275.

Referring to FIG. 4, a user has the ability to select system functions such as reports, administration (i.e. display of user information) as well as maintenance functions. FIG. 17 illustrates a display as the non real time CPU 275 that occurs when an operator selects the reports option shown in FIG. 4. The operator uses this screen to select which of the information stored by the FIG. 3 control system is to be printed. For example, the operator could print a distribution report showing the number of pieces of mail distributed to each of the bins shown in FIG. 2.

FIG. 18 illustrates the display at the non real time CPU 275 when the operator selects the administration option. This display promises the user to enter his name and password or to change the password. The display in FIG. 18 could restrict modification of the information based upon the status of the operator. For example, only an administrator could change the password. FIG. 19 illustrates the display at the non real time CPU 275 when the operator selects the maintenance option.

FIG. 20 is a schematic diagram of the real time statistics maintained by the FIG. 3 controller. As illustrated in FIG. 20, the statistics are maintained in a linked list fashion. FIGS. 21A-21C provide an example of the type of information maintained by the non real time CPU 275.

The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents.

                                      APPENDIX A                                   __________________________________________________________________________     1. .sup. System State Supervisor                                               1.1 Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- ESTOP                                                                 Source       irsEstop, triggered by any of the E-Stop buttons                               interrupts on leading and trailing edge of E-Stop signal        wParam         TRUE = button pressed, FALSE = button reset                     MSG.sub.-- SYS.sub.-- STOP                                                       Source       irsSysStop, triggered by operator pressing stop on the                         system control panel. Leading edge triggered only               MSG.sub.-- MENU.sub.-- STARTUP                                                   Source       SUPV.sub.-- SYS.sub.-- CONSOLE, the non-real time PC. The                      operator                                                                       selected "Start next pass" from the main menu.                  MSG.sub.-- SORT.sub.-- PLAN                                                      Source       SUPV.sub.-- SYS.sub.-- CONSOLE. The operator has chosed a                      sor                                                             MSG.sub.-- FINISHED.sub.-- SORT                                                  Source       SUPV.sub.-- SYS.sub.-- CONSOLE. The operator selected                          "Finished Sort".                                                MSG.sub.-- MAINTENANCE                                                           Source       SUPV.sub.-- SYS.sub.-- CONSOLE. The operator selected a                        maintenance                                                                    function.                                                       MSG.sub.-- HOME.sub.-- OK                                                        Source       Motor Supervisors. Sent in response to a SST.sub.--                            GO.sub.-- HOME                                                                 from SUPV.sub.-- SYS.sub.-- STATE. Sent when the homing                        procedure                                                                      in complete.                                                      wParam       TRUE = homing was successful, FALSE = homing was                               not successful                                                  MSG.sub.-- REV.sub.-- UP.sub.-- OK                                               Source       Motor Supervisors. Sent in response to a SST.sub.--                            REV.sub.-- UP                                                                  from SUPV.sub.-- SYS.sub.-- STATE. Sent when the rev up is                     complete.                                                         wParam       TRUE = rev up was successful, FALSE = rev up failed             MSG.sub.-- JAM                                                                   Source       Any Motor Supervisor. A jam has been detected.                    lParam       pointer to the letter record                                    MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                   Source       Motor Supervisors. Sent in response to a SST.sub.--                            STOP.sub.-- ON.sub.-- JAM.                                                     Sent when the motots have come to a complete stop.                wParam       TRUE = Stopped sucessfully, FALSE = stop has not suceeded                      (this is a serious error)                                       MSG.sub.-- RECOVERED.sub.-- OK                                                   Source       Motor Supervisors. Sent in response to a SST.sub.--                            IS.sub.-- RECOVERED.                                                           Sent when there is no more mail in the "domain" of the                         supervisor (this happens during jam recovery).                  MSG.sub.-- PURGED.sub.-- OK                                                      Source       Motor Supervisors. Sent in response to a SST.sub.--                            IS.sub.-- PURGED.                                                              Sent when there is no more mail in the "domain" of the                         supervisor.                                                     MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                            Source       Motor Supervisors. Sent in response to a SST.sub.--                            RAMP.sub.-- DOWN.                                                              Sent when the motors have come to a complete stop.                wParam       TRUE = ramped down successfully, FALSE = failure ramping                       down (this is a serious error).                                 MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                             Source       Motor Supervisors. Sent in response to a                                       SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS.                   wParam       TRUE = mail is in the supervisor's domain.                                     FALSE = there is no mail in the supervisor's                    __________________________________________________________________________                    domain                                                          1.2. Output Messages                                                           Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- ESTOPPED                                               Dest         Motor Supervisors. Tells them an E-stop has occurred            MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- GO.sub.-- HOME                                         Dest         Motor Supervisors. Tells them to start their homing                            procedure. Each supervisor must return a MSG.sub.--                            HOME.sub.-- OK                                                                 when the homing is complete. Supervisors that don't                            require homing may return a MSG.sub.-- HOME.sub.-- OK                          immediately.                                                    MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- STOPPED                                                Dest         Motor Supervisors. Says we are in state ST.sub.-- STOPPED       MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- IDLE                                                   Dest         Motor Supervisors. Says we are in state ST.sub.-- IDLE          MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- READY                                                  Dest         Motor Supervisors. Says we are in state ST.sub.-- READY         MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- REV.sub.-- UP                                          Dest         Motor Supervisors. Tells them to start rev up procedure;                       turn the motors on, etc. Each motor supervisor must                            return a MSG.sub.-- REV.sub.-- UP.sub.-- OK when the                           motors are up to speed.                                         MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- GRINDING                                               Dest         Motor Supervisors. Says we are in state ST.sub.-- GRINDING      MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- PURGING                                                Dest         Motor Supervisors. Says we are in state ST.sub.-- PURGING.      MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- IS.sub.-- PURGED                                       Dest         Motor Supervisors. Asks a supervisor to return a                               MSG.sub.-- PURGED.sub.-- OK once all mail pieces are out                       of its "domain".                                                MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- STOP.sub.-- ON.sub.-- JAM                              Dest         Motor Supervisors. Says that we are in ST.sub.-- STOPPING.s                    ub.-- ON.sub.-- JAM.                                                           Each motor supervisor must return a MSG.sub.-- STOP.sub.--                     ON.sub.-- JAM.sub.-- OK                                                        once the motors have come to a stop.                            MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                           Dest         Motor Supervisors. Says we are in state ST.sub.-- STOPPED.s                    ub.-- ON.sub.-- JAM                                             MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- JAM.sub.-- RECOVERY                                    Dest         Motor Supervisors. Says we are in state ST.sub.-- JAM.sub.-                    - RECOVERY                                                      MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- IS.sub.-- RECOVERED                                    Dest         Motor Supervisors. Asks a supervisor to return a                               MSG.sub.-- RECOVERED.sub.-- OK as soon as all the mail in                      its "domain"                                                                   is gone.                                                        MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- RAMP.sub.-- DOWN                                       Dest         Motor Supervisors. Tells the motor supervisors to                              ramp down the motors. Each supervisor must return a                            MSG.sub.-- RAMPED.sub.-- DOWN.sub.-- OK as soon as the                         motors have come to                                                            a stop.                                                         MSG.sub.-- SYS.sub.-- STATE                                                      wParam       SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS                    Dest         Motor Supervisors. Asks a supervisor whether there                             are any mail pieces in its domain. Each supervisor                             should respond immediately with a MSG.sub.-- MAIL.sub.--                       IN.sub.-- SYS.                                                  __________________________________________________________________________     2. .sup. Carrier Scheduler                                                     2.1. Input Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SHUTDOWN                                                            MSG.sub.-- CARRIER.sub.-- REQUEST                                                Source       Feeder supervisors: which feeder wants a carrier                  wParam       sizeof (LETTER)                                                   lParam       pointer to a LETTER structure                                   MSG.sub.-- CANCEL.sub.-- REQUEST                                                 Source       Feeder supervisors: which feeder doesnt want a carrier            wParam       sizeof (LETTER)                                                   lParam       pointer to a LETTER structure                                   2.2.Output Messages                                                            MSG.sub.-- INCOMING                                                                           This tells the feeder that the letter has been scheduled                       for liftoff and will be moving shortly                            wDest        which feeder made the original request                            wParam       sizeof (LETTER)                                                   lParam       pointer to a LETTER structure                                   3. .sup. Manual Feed Function                                                  3.1.Input Messages                                                             The manual feed supervisor processes many messages, mostly from its own        ISRs. Extra parameters are noted where appropriate:                            __________________________________________________________________________     Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- MAIL.sub.-- PRESENT                                                   Source       ISR Mail Present. The mail present sensor has been                             interrupted.                                                      wParam       TRUE = sensor is bocked, FALSE = sensor is unblocked            MSG.sub.-- MAILSTOP                                                                           Contains the mail stop                                            Source       Manual Feed Terminal ISR                                          lParam       pointer to the Zip+ 4 value                                     MSG.sub.-- WEIGHT                                                                             Contains the weight of the piece                                  Source       Manual Feed Scale ISR                                             wParam       the weight in 100ths of an oz.                                  MSG.sub.-- HAND.sub.-- AWAY                                                      Source       the hand away sensor ISR has changed                               wParam      TRUE = hand is out of the way, FALSE = hand is in the                          way.                                                            MSG.sub.-- CANCEL                                                                             the operator wants to cancel the last typed value.                Source       the manual feed terminal                                        MSG.sub.-- CLEAR                                                                 Source       the cleated belt motor ack. This means the cleated belt                        is back in position to feed another mail piece.                 MSG.sub.-- POLL                                                                               This message is used to poll sensors.                             Dest         Manual Feed Supervisor                                            Source       Manual Feed Supervisor                                          MSG.sub.-- CATCHUP.sub.-- ENTER                                                  Source       Catchup enter sensor isr. Triggers on both negative and                        positive transitions.                                           MSG.sub.-- CATCHUP.sub.-- CLEAR                                                  Source       Catchup motor ack isr. The cleated belt is back                 __________________________________________________________________________                    home.                                                           3.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- CARRIER.sub.-- REQUEST                                                             Asks the carrier scheduler to feed this mail                                   piece!                                                            lParam       Pointer to a LETTER structure for the new                                      mail piece.                                                       Source       Indicates which feeder made the request                           Dest         Carrier Scheduler Supervisor                                    MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Man Feed Supervisor.                                              Dest         Man Feed Supervisor.                                            MSG.sub.-- INCOMING                                                              Dest         Read/Print Supervisor. This message tells the read/print                       supervisor that a letter had been fed and is on its                            way.                                                              lParam       pointer to a letter structure.                                  __________________________________________________________________________      (NOTE: see section 2. for details on the following messages)                   MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                           MSG.sub.-- HOME.sub.-- OK                                                      MSG.sub.-- REV.sub.-- UP.sub.-- OK                                             MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                 MSG.sub.-- PURGED.sub.-- OK                                                    MSG.sub.-- RECOVERED.sub.-- OK                                           

    4. .sup. Auto Feed Supervisor                                                  4.1.Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- MAIL.sub.-- PRESENT                                                   wSource      mail present sensor ISR. Triggers on both negative and                         positive transitions.                                             wParam       TRUE = mail is present (sensor is blocked)                                     FALSE = mail is not present (sensor is not blocked)             MSG.sub.-- CLEAR                                                                 wSource      auto feed singulator motor ack ISR. The letter has moved                       clear off the singulator roller.                                MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Auto Feed Supervisor.                                             Dest         Auto Feed Supervisor.                                           MSG.sub.-- AF.sub.-- CATCHUP.sub.-- ACK                                          Source       auto feed catchup motor ack ISR. The motor has completed                       a command.                                                      __________________________________________________________________________     4.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     (Same as the Manual Feed Output Messages)                                      5. .sup. Read/Print Supervisor                                                 5.1.Input Messages                                                             Mgessage                                                                         Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- INCOMING                                                              Source       Manual or Automatic feeder Supervisor. Tells how                               read/print supervisor that a letter has been fed onto                          the induction pich belts and is on its way                        wParam       size.sub.-- of (LETTER)                                           lParam       pointer to a letter record                                      MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Read/Print Supervisor.                                            Dest         Read/Print Supervisor.                                          __________________________________________________________________________     5.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Read/Print Supervisor.                                            Dest         Read/Print Supervisor.                                          MSG.sub.-- INCOMING                                                              Dest         Inserter Supervisor. This message tells the inserter                           supervisor that a letter has been fed and is on its                            way.                                                              lParam       pointer to a letter structure.                                  __________________________________________________________________________      (NOTE: see section 2. for details on the following messages)                   MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                           MSG.sub.-- HOME.sub.-- OK                                                      MSG.sub.-- REV.sub.-- UP.sub.-- OK                                             MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                 MSG.sub.-- PURGED.sub.-- OK                                                    MSG.sub.-- RECOVERED.sub.-- OK                                           

    6.  .sup. Inserter Supervisor                                                  6.1.Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- INS.sub.-- MOTOR.sub.-- ACK                                           Source       inserter motor ack isr. This message is sent when the                          motor has completed a command.                                  MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Inserter Supervisor.                                              Dest         Inserter Supervisor.                                            MSG.sub.-- INCOMING                                                              Source       Read/Print Supervisor. Tells the inserter supervisor                           that a letter is on its way                                       wParam       size.sub.-- of (LETTER)                                           lParam       pointer to a letter record                                      __________________________________________________________________________     6.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- JAM                                                                   wParam       Jam error code, letter was too late or too early                  lParam       Jam Location                                                    MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Inserter Supervisor.                                              Dest         Inserter Supervisor.                                            MSG.sub.-- INCOMING                                                              Dest         Stacker Supervisor. Tells the stacker supervisor                               that a letter is on its way.                                      wParam       size.sub.-- of (LETTER)                                           lParam       pointer to a letter record                                      __________________________________________________________________________      (NOTE: see section 2. for details on the following messages)                   MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                           MSG.sub.-- HOME.sub.-- OK                                                      MSG.sub.-- REV.sub.-- UP.sub.-- OK                                             MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                 MSG.sub.-- PURGED.sub.-- OK                                                    MSG.sub.-- RECOVERED.sub.-- OK                                           

    7. .sup. Stacker Scheduler                                                     7.1.Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- STK.sub.-- MOTOR.sub.-- ACK                                           Source       stack motor ack isr. This message is sent when the                             motor has completed a command.                                  MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Stacker Supervisor.                                               Dest         Stacker Supervisor.                                             MSG.sub.-- INCOMING                                                              Source       Inserter Supervisor. Tells the stacker supervisor                              that a letter is on its way                                       wParam       size.sub.-- of (LETTER)                                           lParam       pointer to a letter record                                      __________________________________________________________________________     7.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- POLL                                                                               Used to poll a sensor.                                            Source       Stacker Supervisor.                                               Dest         Stacker Supervisor.                                             MSG.sub.-- INCOMING                                                              Dest         System Console Supervisor (non-real time PC). Tells the                        system console and database that the letter has been                           sorted into a bin.                                                wParam       size.sub.-- of (LETTER)                                           lParam       pointer to a letter record                                      __________________________________________________________________________      (NOTE: see section 2. for details on the following messages)                   MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                           MSG.sub.-- HOME.sub.-- OK                                                      MSG.sub.-- REV.sub.-- UP.sub.-- OK                                             MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                  MSG.sub.-- PURGED.sub.-- OK                                                   MSG.sub.-- RECOVERED.sub.-- OK                                           

    8. .sup. Error/Jam Supervisor                                                  8.1.Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- INIT                                                                               Initialize variables and data structures                          Source       Boot strap program                                              MSG.sub.-- SYS.sub.-- STATE                                                                   (See section 2. for details on how motor supervisors                           must respond to MSG.sub.-- SYS.sub.-- STATE messages)           MSG.sub.-- JAM                                                                   Source       jam sensor isr. One of the sensors detected a jam.                wParam       sizeof (JAM.sub.-- DATA)                                          lParam       pointer to a letter record and a cause code                     __________________________________________________________________________     8.2.Output Messages                                                            Message                                                                          Parameter    Description                                                     __________________________________________________________________________     MSG.sub.-- JAM                                                                   Dest         System State Supervisor. Tells the system state                                supervisor                                                                     that a jam has occurred.                                          lParam       pointer to a letter record                                      MSG.sub.-- KILL.sub.-- LETTER                                                    Dest         Motor Supervisors. Tells each motor supervisor to search                       its data for the letter specified in the lParam. If                            the letter is present, delete it from the data.                                MSG.sub.-- KILL.sub.-- LETTER is sent when the operator                        removes a piece                                                                from the induction line after a jam.                              lParam       pointer to a letter record                                      __________________________________________________________________________      (NOTE: see section 2. for details on the following messages)                   MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS                                           MSG.sub.-- HOME.sub.-- OK                                                      MSG.sub.-- REV.sub.-- UP.sub.-- OK                                             MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK                                 MSG.sub.-- PURGED.sub.-- OK                                                    MSG.sub.-- RECOVERED.sub.-- OK                                           

    9. .sup. System Console                                                        9.0. Typical Format for messages                                               Header [Data]                                                                  The header will contain what type of message. The type will                    determine what kind of data follows. Data is optional.                         Input Messages (Real-Time to System Console)                                   RTMSG.sub.-- HELLO                                                             Lets the system console establish a session                                                   .sup. when the RT boots up.                                     RTMSG.sub.-- LETTER                                                            Contains letter information, 4 letters/sec max                                 RTMSG.sub.-- JAM                                                               Letter that was jammed and its location                                        RTMSG.sub.-- TIMELINE                                                          Each event that needs to be recorded                                               (E-Stops, Jams, Maintenance)                                               __________________________________________________________________________      NOTE: HMS, Advantage to splitting the status up is you need only 1 case        statement to figure out where to put the information (simplifies the           code).                                                                         If you combine everything then you must interpret a flag. (very, very          messy and very very time consuming.)                                     

    RTMSG.sub.-- SENDNAME                                                          Contains a request for a search on a partial name.                             RTMAG.sub.-- PERFORMANCE                                                       Performance statistics from the OS9 system.                                         (Jim knows about this???)                                                 Output Messages (System Console to Real-Time)                                  SYSMSG.sub.-- STARTSORT                                                        Notifys RT that sortplan records will follow,                                       contains the Run ID.                                                      __________________________________________________________________________      NOTE: The Run ID is generated by the system console and passed to the RT       in this message.                                                         

    SYSMSG.sub.-- SORTPLAN                                                         Contains sort plan record                                                      SYSMSG.sub.-- ENDSORT                                                          Tells the RT computer that a sort plan is                                                     .sup. finished loading.                                         SYSMSG.sub.-- STARTNAME                                                        Notifys RT that Employee records will follow,                                  SYSMSG.sub.-- NAME                                                             Contains Employee record record                                                SYSMSG.sub.-- ENDNAME                                                          Tells the RT computer that done sending Employee                                  records.                                                                    SYSMSG.sub.-- STOPSORT                                                         Contains sort plan record                                                      SYSMSG.sub.-- STARTUP                                                          Places RT into Homing condition                                                SYSMSG.sub.-- FINISHED                                                         Finished sort after operator stops machine                                     __________________________________________________________________________     9.1 Input Messages                                                             Message                                                                          Parameter    Description                                                     __________________________________________________________________________     RTMSG.sub.-- HELLO                                                                            This is a message to the system console                         containing the Machine ID. This will become                                    more important when we have multiple sorters                                   and computers.                                                                   wParam       wMachineID                                                        lParam       Not used                                                          data record  Not used                                                        RTMSG.sub.-- JAM                                                                              This is a message to the system console                                        containing Jam information. This information                                   will be placed in the database.                                   wParam       Not used                                                          lParam       Not used                                                          data record  JAM.sub.-- REC                                                  RTMSG.sub.-- LETTER                                                                           This is a message to the system console                                        containing letter information. Reject, Code values,             Destination, Fed by, Physical Attributes make up                               the letter record. This information will be placed                                            in the database.                                                  wParam       Not used                                                          lParam       Not used                                                          data record  LETTER.sub.-- REC                                               RTMSG.sub.-- TIMELINE                                                                         This is a message to the system console                                        containing Timeline information. Startup, E-Stops,                             Maintenance, Jams make up the time line for a                   run. This information will be placed in the database.                            wParam       Not used                                                          lParam       Not used                                                          data record  TIMELINE.sub.-- REC                                             RTMSG.sub.-- SENDNAME                                                          This is a message to the system console containing                                            a request for a search on a partial name. This                  information will be used to return a list of names                             for the manual feed operator to select from.                                     wParam       Not used                                                          lParam       Not used                                                          data record  EMPLOYEE.sub.-- REC                                             __________________________________________________________________________     9.2.Output Messages from Real-time to System console                           Message                                                                          Parameter    Description                                                     __________________________________________________________________________     SYSMSG.sub.-- STARTUP                                                                         Tells the RT computer that the operator performed               a menu startup. This will bring the machine to the                             homing state.                                                                    wParam       Not used                                                          lParam       Not used                                                          data record  Not used                                                        SYSMSG.sub.-- STARTSORT                                                                       Tells the RT computer that a sort plan is to be loaded.         Also lets the RT know what the Run ID should be.                                 wParam       wRunID - Generated by system console                              lParam       Not used                                                          data record  Not used                                                        SYSMSG.sub.-- SORTPLAN                                                                        Contains the sort plan that the RT computer                                    will use to do its stuff. Only one pass will                                 be loaded at a time.                                                wParam       Not used                                                          lParam       Not used                                                          data record  BIN.sub.-- REC                                                  SYSMSG.sub.-- ENDSORT                                                                         Tells the RT computer that a sort plan is finished              loading.                                                                         wParam       Number of BIN.sub.-- REC sent                                     lParam       Not used                                                          data record  Not used                                                        SYSMSG.sub.-- STARTNAME                                                                       Notifys RT that Employee records will follow,                     wParam       Not used                                                          lParam       Not used                                                          data record  Not used                                                        SYSMSG.sub.-- NAME                                                                            Contains Employee record including the mailstop.                  wParam       Not used                                                          lParam       Not used                                                          data record  EMPLOYEE.sub.-- REC                                             SYSMSG.sub.-- ENDNAME                                                                         Tells the RT computer that done sending Employee                               records.                                                          wParam       Number of EMPLOYEE.sub.-- REC sent                                lParam       Not used                                                          data record  Not used                                                        SYSMSG.sub.-- FINISHED                                                                        Tells the RT computer that the operator no                                     longer wants to use the current sort plan.                        wParam       Not used                                                          lParam       Not used                                                          data record  Not used                                                        __________________________________________________________________________

                                      APPENDIX B                                   __________________________________________________________________________     Present                    Next                                                State     Inputs           State     Outputs                                   __________________________________________________________________________     Any State MSG.sub.-- ESTOP           SST.sub.-- ESTOPPED to:                                                        Motor Supervisors.                        IDLE      MSG.sub.-- SYS.sub.-- START from                                                                HOMING    SST.sub.-- GO.sub.-- Home to:                       isrSysStart &              Motor Supervisors.                                  MSG.sub.-- MENU.sub.-- STARTUP                                                 from SUPV.sub.-- SYS.sub.-- CONSOLE                                            MSG.sub.-- ESTOP;TRUE                                                                           ESTOP.sub.--                                                                   HOMING                                              HOMING    MSG.sub.-- HOME.sub.-- OK;TRUE from:                                                            STOPPED   SST.sub.-- STOPPED to:                              Motor Supervisors          Motor Supervisors.                                                             DisableStart ( );                                   MSG.sub.-- HOME.sub.-- OK;FALSE                                                                 IDLE      SST.sub.-- HOME.sub.-- FAILED to:                   from any:                  SysConsole                                          Motor Supervisor                                                               MSG.sub.-- ESTOP;TRUE                                                                           ESTOP.sub.--                                                                   HOMING                                              ESTOP.sub.--                                                                             MSG.sub.-- ESTOP;FALSE                                                                          IDLE      SST.sub.-- IDLE to:                       HOMING                               Motor Supervisors.                        STOPPED   MSG.sub.-- SORT.sub.-- PLAN from:                                                               READY     SST.sub.-- READY to:                                SYS.sub.-- CONSOLE         Motor Supervisors                                                              EnableStart( )                                      MSG.sub. -- ESTOP;TRUE                                                                          ESTOP.sub.--                                                                   STOPPED                                             ESTOP.sub.--                                                                             MSG.sub.-- ESTOP;FALSE                                                                          STOPPED   SST.sub.-- STOPPED to:                    STOPPED                              Motor Supervisors.                        READY     MSG.sub.-- SYS.sub.-- START from:                                                               REV.sub.-- UP                                                                            SST.sub.-- REV.sub.-- UP to:                        isrSysStart( )             Motor Supervisors                                   MSG.sub.-- FINISHED.sub.-- SORT from:                                                           STOPPED   SST.sub.-- STOPPED to:                              SYS.sub.-- CONSOLE         Motor Supervisors.                                                             DisableStart( )                                     MSG.sub.-- MAINTENANCE                                                                          MAINTENANCE                                                   MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    ESTOPPED.sub.--                                                                          MSG.sub.-- ESTOP;FALSE &                                             AFT.sub.-- READY                                                                         MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS;FALSE                                                      READY     SST.sub.-- READY to:                                from all Motor Supervisors Motor Supervisors.                                                             EnableStart( );                                     MSG.sub.-- ESTOP;FALSE &                                                                        STOPPED.sub.-- ON.sub.--                                                                 SST.sub.-- STOPPED.sub.-- ON.sub.--                                            JAM to:                                             MSG.sub.-- MAIL.sub.-- IN.sub.-- SYS;TRUE                                                       JAM       Motor Supervisors.                                  from any Motor Supervisor  EnableStart( );                           REV.sub.-- UP                                                                            MSG.sub.-- REV.sub.-- UP.sub.-- OK;TRUE                                                         GRINDING  SST.sub.-- GRINDING to:                             from: Motor Supervisors    Motor Supervisors.                                                             nWorkingState = GRINDING                            MSG.sub.-- REV.sub.-- UP.sub.-- OK;FALSE                                                        READY     SST.sub.-- READY to:                                from any:                  Motor Supervisors.                                  Motor Supervisor                                                               MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    GRINDING  MSG.sub.-- SYS.sub.-- STOP from:                                                                PURGING   SST.sub.-- PURGING to:                              isrSyssStop( )             Motor Supervisors.                                                             SST.sub.-- IS.sub.-- PURGED to: AF,                                            MF                                                                             nWorkingState = PURGING                                                        BlinkReadyLight( );                                 MSG.sub.-- JAM from:                                                                            STOPPING.sub.--                                                                          SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                           to:                                                 SupvErrJam       ON.sub.-- JAM                                                                            Motor Supervisors                                   MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    STOPPING.sub.--                                                                          MSG.sub.-- STOP.sub.-- ON.sub.-- JAM.sub.-- OK:T                                                STOPPED.sub.--                                                                           SST.sub.-- STOPPED.sub.-- ON.sub.--                                            JAM to:                                   ON.sub.-- JAM                                                                            From: Motor Supervisors                                                                         ON.sub.-- JAM                                                                            Motor Supervisors.                                                             EnableStart( );                                     MSG.sub. -- STOP.sub.-- ON.sub.-- JAM.sub.-- OK:F                                               ESTOPPED.sub.--                                                                          MSG.sub.-- ESTOP to                                 From any:        AFT.sub.-- READY                                                                         SupvSysState (fake ESTOP!)                          Motor Supervisor                                                               MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    STOPPED.sub.--                                                                           MSG.sub.-- SYS.sub.-- START from:                                                               JAM.sub.--                                                                               SST.sub.-- JAM.sub.-- RECOVERY to:        ON.sub.-- JAM                                                                            isrSysStart( )   RECOVERY  Motor Supervisor.                                                              SST.sub.-- IS.sub.-- RECOVERED to:                                             MF, AF                                              MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    JAM.sub.--                                                                               MSG.sub.-- RECOVERED.sub.-- OK from:                                                            JAM.sub.--                                                                               SST.sub.-- IS.sub.-- RECOVERED to:        RECOVERY  MF and AF        RECOVERY  ReadPrint                                           MSG.sub.-- RECOVERED.sub.-- OK from:                                                            JAM.sub.--                                                                               SST.sub.-- IS.sub.-- RECOVERED to:                  ReadPrint        RECOVERY  Inserter                                            MSG.sub.-- RECOVERED.sub.-- OK from:                                                            JAM.sub.--                                                                               SST.sub.-- IS.sub.-- RECOVERED to:                  Inserter         RECOVERY  Stacker                                             MSG.sub.-- RECOVERED.sub.-- OK from:                                                            REV.sub.-- UP                                                                            SST.sub.-- REV.sub.-- UP to:                        Stacker &                  Motor Supervisors.                                  nWorkingState = GRINDING                                                       MSG.sub.-- RECOVERED.sub.-- OK from:                                                            RAMP.sub.-- DOWN                                                                         SST.sub.-- RAMP.sub.-- DOWN to:                     Stacker &                  Motor Supervisors.                                  nWorkingState = PURGING                                                        MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    PURGING   MSG.sub.-- PURGED.sub.-- OK from:                                                               PURGING   SST.sub.-- IS.sub.-- PURGED to:                     MF and AF                  ReadPrint                                           MSG.sub.-- PURGED.sub.-- OK from:                                                               PURGING   SST.sub.-- IS.sub.-- PURGED to:                     ReadPrint                  Inserter                                            MSG.sub.-- PURGED.sub.-- OK from:                                                               PURGING   SST.sub.-- IS.sub.-- PURGED to:                     Inserter                   Stacker                                             MSG.sub.-- PURGED.sub.-- OK from:                                                               RAMP.sub.-- DOWN                                                                         SST.sub.-- RAMP.sub.-- DOWN to:                     Stacker                    Motor Supervisors.                                  MSG.sub.-- JAM from SupvErrJam                                                                  STOPPING.sub.--                                                                          SST.sub.-- STOP.sub.-- JAM to:                                       ON.sub.-- JAM                                                                            Motor Supervisors.                                  MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    RAMP.sub.-- DOWN                                                                         MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK:T                                                         READY     SST.sub.-- READY to:                                From: Motor Supervisors    Motor Supervisors.                                  MSG.sub.-- RAMP.sub.-- DOWN.sub.-- OK:F                                                         ESTOPPED.sub.--                                               From any:        AFT.sub.-- READY                                              Motor Supervisor                                                               MSG.sub.-- ESTOP ESTOPPED.sub.--                                                                AFT.sub.-- READY                                    MAINTENANCE                                                                              Undefined        Undefined Undefined                                 __________________________________________________________________________

                                      APPENDIX C                                   __________________________________________________________________________     Present                Next                                                    State    Inputs        State           Outputs                                 __________________________________________________________________________     ST.sub.-- IDLE                                                                          SST.sub.-- GO.sub.-- HOME                                                                    ST.sub.-- HOMING                                                                               Home Cleat Belt                                  SST.sub.-- ESTOPPED                                                                          ST.sub.-- IDLE                                                   SST.sub.-- GRINDING                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- Piece                                                      bWaitingForClear =                                                              TRUE                                                                           ThisLetter = NULL                                                              LastLetter = NULL                                                              CLEAR.sub.-- MF.sub.-- FLAGS           ST.sub.-- HOMING                                                                        MSG.sub.-- POLL                                                                              ST.sub.-- IDLE  MSG.sub.-- HOME.sub.-- OK:TRUE                    && bHomed                     to SysState                                     MSG.sub.-- POLL                                                                              ST.sub.-- HOMING                                                                               MSG.sub.-- POLL to ManFeed                        && !bHomed                                                                    SST.sub.-- ESTOPPED                                                                          ST.sub.-- IDLE                                          ST.sub.-- WAITING.sub.--                                                                bPurging      ST.sub.-- IDLE                                           FOR.sub.-- PIECE                                                                        Any msg triggers                                                              MSG.sub.-- MAIL.sub.-- PRESENT                                                               ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       Trigger Scale                                    MSG.sub.-- MAILSTOP                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      Letter->mailstop                                 SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         Motors weren't moving                            SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- WAITING.sub.--                                                                MSG.sub.-- MAILSTOP                                                                          ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       Letter->mailstop flag                    TO.sub.-- START                                                                        MSG.sub.-- WEIGHT                                                                            ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       Letter->weight flag                              Weight && Mailstop                                                                           ST.sub.-- WAITING.sub.-- FOR.sub.-- CLEAR                                                      MSG.sub.-- CARRIER.sub.-- REQUEST                && MailPresent &&              to CarrSched                                    HandAway                       nSentNotReceived++                                                             ThisLetter = NULL                                                              bWaitingForClear =                                                             TRUE                                            MSG.sub.-- CANCEL                                                                            ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      CLEAR.sub.-- MF.sub.-- FLAGS                     SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         Motors weren't moving                            SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- WAITING.sub.--                                                                MSG.sub.-- CLEAR &&                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      bWaitingForClear =                      FOR.sub.-- CLEAR                                                                         !bPurging                     FALSE                                                                          CLEAR.sub.-- MF.sub.-- FLAGS                    MSG.sub.-- CLEAR &&                                                                          ST.sub.-- IDLE  bWaitingForClear =                                                              FALSE                                           SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        Stop Motors.                                                                    MSG.sub.-- POLL to ManFeed                                                     bCleatStopped = FALSE                           SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                                                             bWaitingForClear=TRUE                                                           bCleatStopped = TRUE                   ST.sub.-- STOPPING                                                                      MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        MSG.sub.-- POLL to ManFeed               .sub.-- ON.sub.-- JAM                                                                   !bCleatStopped                                                                MSG.sub.-- POLL &&                                                                           sT.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         bCleatStopped = TRUE                              bCleatStopped                                                                 SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.--                                                             bCleatStopped = TRUE                    ST.sub.-- STOPPED                                                                       SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- JAM.sub.-- RECOVERY                                                                  Cleat Home-Slow                          .sub.-- ON.sub.-- JAM                                                                   && !bWaitingForClear                                                          SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- IDLE                                                    && !bWaitingForClear                                                          SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  ST.sub.-- JAM.sub.--                                                                    MSG.sub.-- CLEAR                                                                             ST.sub.-- IDLE  bWaitingForClear=FALSE                   RECOVERY                                                                               SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         bWaitingForClear=TRUE                   ST.sub.-- ESTOPPED                                                                      SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- IDLE  CLEAR.sub.-- MF.sub.-- FLAGS                      && !bWaitingForClear                                                          SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                            && bWaitingForClear                                                           SST.sub.-- READY                                                                             ST.sub.-- IDLE  CLEAR.sub.-- MF.sub.-- FLAGS            __________________________________________________________________________

                                      APPENDIX D                                   __________________________________________________________________________     Present                Next                                                    State    Inputs        State           Outputs                                 __________________________________________________________________________     Any      SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS                                               Same            MSG.sub.-- MAIL.sub.-- IN.sub.--                                               SYS:TRUE                                          no mail in feeder             to SupvSysState                                 SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS                                               Same            MSG.sub.-- MAIL.sub.-- IN.sub.--                                               SYS:FALSE                                         & there is mail in            to SupvSysState                                  the feeder                                                                    MSG.sub.-- INCOMING from                                                                     Same            NextCatchupLetter =                               Carrier Scheduler             Incoming letter.                                                               nSentNotReceived--                              SST.sub.-- IS.sub.-- RECOVERED                                                               Same            bJamRecovery = TRUE                                                             MSG.sub.-- POLL to ManFeed                      SST.sub.-- IS.sub.-- PURGING                                                                 Same            bPurging = TRUE                                                                 MSG.sub.-- POLL to ManFeed              NOTE: No mail in feeder means:                                                     CatchupLetter == NULL AND NextCatchupLetter == NULL                            AND nSentNotReceived == 0                                            

    ST.sub.-- STOPPED                                                                       SST.sub.-- REV.sub.-- UP                                                                     ST.sub.-- REV.sub.-- UP                                                                        Start Catchup Belt                                                              bPurging = FALSE                                                               bRampedDown = FALSE                                                            Clear Letter Ptrs.                              SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                       ST.sub.-- REV.sub.-- UP                                                                 MSG.sub.-- UP.sub.-- TO.sub.-- SPEED                                                         ST.sub.-- REV.sub.-- UP                                                                        MSG.sub.-- REV.sub.-- UP.sub.--                                                OK:TRUE                                                                         to SysState                                     SST.sub.-- GRINDING                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                        SST.sub.-- RAMP.sub.-- DOWN                                                                  ST.sub.-- RAMP.sub.-- DOWN                                                                     Start to stop belts                                                             bRampedDown                                                                     = FALSE                                                                       bJamRecovery                                                                    = FALSE                                        SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                       ST WAITING                                                                              MSG.sub.-- POLL &&                                                                           ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      MSG.sub.-- PURGED.sub.-- OK:True         FOR.sub.-- PIECE                                                                        bPurging == TRUE              to SysState                                      && no mail coming             bPurging = FALSE                                 from cleat area                                                               MSG.sub.-- POLL &&                                                                           ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       MSG.sub.-- RECOVERED OK:                          bJamRecovery == TRUE          TRUE to SysState                                 && no mail coming             bJamRecovery                                     from cleat area                = FALSE                                        MSG.sub.-- POLL                                                                              ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      MSG.sub.-- POLL to ManFeed                        && Mail coming                                                                 from cleat area                                                                && !bJamRecovery                                                               && !bPurging                                                                  MSG.sub.-- POLL &&                                                                           ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       ThisCatchupLetter =                               && NextLetter !=              NextCatchupLetter                                NULL                          NextCatchupLetter                                                               = NULL                                         MSG.sub.-- INCOMING                                                                          ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       ThisCatchupLetter =                               && NextLetter !=              NextCatchupLetter                                NULL                          NextCatchupLetter                                                               = NULL                                         SST.sub.-- RAMP.sub.-- DOWN                                                                  ST.sub.-- RAMP.sub.-- DOWN                                                                     bJamRecovery = FALSE                                                            Stop Catchup belt                                                              bRampedDown                                                                     = FALSE                                        SST.sub.-- REV.sub.-- UP                                                                     ST.sub.-- REV.sub.-- UP                                                                        bJamRecovery = FALSE                                                            bPurging = FALSE                                                               Clear Letter ptrs.                                                             Start Motors                                    SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        Stop Motors                                                                    MSG.sub.-- POLL to ManFeed                       SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                       NOTE: No mail coming from cleat area means:                                        CatchupLetter == NULL AND NextCatchupLetter == NULL                            AND MFState == ST.sub.-- IDLE                                             ST.sub.-- WAITING.sub.--                                                                MSG.sub.-- CATCHUP.sub.-- ENTER                                                              ST.sub.-- WAITING.sub.-- FOR.sub.-- CLEAR                                                      ThisCatchupLetter->                      TO.sub.-- START                                                                         && !bJamRecovery              thickness =  read                                                              thickness.                                                                     MSG.sub.-- INCOMING to                                                         ReadPrint                                                                      Start acceleration.                             MSG.sub.-- CATCHUP.sub.-- ENTER                                                              ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      ThisCatchupLetter->                               && bJamRecovery               thickness = read                                                               thickness.                                                                     MSG.sub.-- INCOMING to                                                         ReadPrint.                                                                     MSG.sub.-- POLL to ManFeed                      SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        Stop Motors.                                                                   MSG.sub.-- POLL to ManFeed                       SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- WAITING.sub.--                                                                SST.sub.-- PURGING                                                                           ST.sub.-- WAITING.sub.-- FOR.sub.-- CLEAR                                                      Stop feeding.                            FOR.sub.-- CLEAR                                                                       MSG.sub.-- CATCHUP.sub.-- CLEAR                                                              ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      MSG.sub.-- POLL to                                && (bPurging ||                                                                            ManFeed                                          bJamRecovery)                                                                 SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        Stop Motors.                                                                    MSG.sub.-- POLL to ManFeed                      SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- STOPPING                                                                      MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        MSG.sub.-- POLL to ManFeed               .sub.-- ON.sub.-- JAM                                                                   |(bCleatStopped &&                                                    bRampedDown)                                                                  MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        MSG.sub.-- STOPPED.sub.-- ON.sub.--                                             JAM.sub.-- OK                                    bCleatStopped &&              TRUE to SysState                                 bRampedDown                                                                   SST.sub.-- STOPPED ON.sub.-- JAM                                                             ST.sub.-- STOPPED ON.sub.-- JAM                                  SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED ON.sub.-- JAM                         ST.sub.-- STOPPED                                                                       SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      Go to recover speed.                     .sub.-- ON.sub.-- JAM                                                                   && NoMail                     bRampedDown = FALSE                              && bPurging                   MSG.sub.-- POLL to ManFeed                      SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      Go to recover speed.                              && No Mail                    bRampedDown = FALSE                              && !bPurging                                                                  SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- WAITING.sub.-- TO.sub.-- START                                                       Go to recover speed.                              && Mail in feeder                                                             SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                   NOTE: No mail means there aren't any letters waiting to be caught up:              CatchupLetter == NULL && NextCatchupLetter == NULL.                       ST.sub.-- RAMP.sub.--                                                                   MSG.sub.-- POLL &&                                                                           ST.sub.-- RAMP.sub.-- DOWN                                                                     MSG.sub.-- POLL to ManFeed               DOWN     !bRampedDown                                                                  MSG.sub.-- POLL && Catchup                                                                   ST.sub.-- STOPPED                                                                              MSG.sub.-- RAMP.sub.-- DOWN.sub.--                                             OK:TRUE                                           bRamped Down                                                                  SST.sub.-- READY                                                                             ST.sub.-- STOPPED                                                SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                       ST.sub.-- ESTOPPED                                                                      SST.sub.-- READY                                                                             ST.sub.-- STOPPED                                                SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  __________________________________________________________________________

    __________________________________________________________________________     APPENDIX E                                                                     PRESENT                Next                                                    STATE    Inputs        State           Outputs                                 __________________________________________________________________________     ST.sub.-- IDLE                                                                          SST.sub.-- GO.sub.-- HOME                                                                    ST.sub.-- IDLE  MSG.sub.-- HOMED.sub.-- OK:TRUE                  SST.sub.-- ESTOPPED                                                                          ST.sub.-- IDLE                                                   SST.sub.-- GRINDING                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      bWaitingForClear =                                                             FALSE                                                                          ThisLetter = NULL                                                              LastLetter = NULL                       ST.sub.-- WAITING.sub.--                                                                bPurging      ST.sub.-- IDLE                                          FOR.sub.-- PIECE                                                                        Any msg triggers                                                               MSG.sub.-- MAIL.sub.-- PRESENT                                                               ST.sub.-- WAITING.sub.-- FOR.sub.-- CLEAR                                                      MSG.sub.-- CARRIER.sub.-- REQUEST                                              to CarrSched                                                                   nSentNotReceived++                                                             ThisLetter = NULL                                                              bWaitingForClear =                                                             TRUE                                             SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         Motor's weren't moving                           SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- WAITING.sub. --                                                               MSG.sub.-- CLEAR &&                                                                          ST.sub.-- WAITING.sub.-- FOR.sub.-- PIECE                                                      bWaitingForClear =                      FOR.sub.-- CLEAR                                                                        !bPurging                     FALSE                                            MSG.sub.-- CLEAR &&                                                                          ST.sub.-- IDLE  bWaitingForClear =                               bPurging                      FALSE                                            SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        Stop Motors.                                                                   MSG.sub.-- POLL to ManFeed                       SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- STOPPING                                                                      MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                        MSG.sub.-- POLL to ManFeed              .sub.-- ON.sub.-- JAM                                                                   Singulator not                                                                 stopped.                                                                       MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                           Singulator stopped                                                             SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  ST.sub.-- STOPPED                                                                       SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- JAM.sub.-- RECOVERY                                                                  Do Slower Speed                         .sub.-- ON.sub.-- JAM                                                                   && bWaitingForClear           Start to finish                                                                singulating any                                                                previous piece                                                                 still in singulator.                             SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- IDLE                                                   && !bWaitingForClear                                                           SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  ST.sub.-- JAM.sub.--                                                                    MSG.sub.-- CLEAR                                                                             ST.sub.-- IDLE  bWaitingForClear=FALSE                  RECOVERY SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         bWaitingForClear=TRUE                   ST.sub.-- ESTOPPED                                                                      SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- IDLE  CLEAR.sub.-- MF.sub.-- FLAGS                     && !bWaitingForClear                                                           SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                           && bWaitingForClear                                                            SST.sub.-- READY                                                                             ST.sub.-- IDLE                                          __________________________________________________________________________

    __________________________________________________________________________     APPENDIX F                                                                     Present                Next                                                    State    Inputs        State    Outputs                                        __________________________________________________________________________     ST.sub.-- WAIT.sub.--                                                                   Leading edge at                                                                              ST.sub.-- WAIT.sub.--                                                                   GnAccelDirec, GwCatchupTime                    ON.sub.-- ENTER                                                                         AutoFeed Catchup Enter                                                                       ON.sub.-- INSIDE                                        ST.sub.-- WAIT.sub.--                                                                   (Trailing edge at                                                                            ST.sub.-- WAIT.sub.--                                                                   isr: count=GwCatchupTime                       ON.sub.-- INSIDE                                                                        AutoFeed Catchup Enter)                                                                      ON.sub.-- ACK                                                                           (isr: AF.sub.-- MOTOR.sub.-- ACCEL                      AND (AutoFeed Catchup  or AF.sub.-- MOTOR.sub.-- DECEL)                        leaving is blocked)                                                            (Trailing edge at                                                                            ST.sub.-- WAIT.sub.--                                            AutoFeed Catchup Enter)                                                                      ON.sub.-- LEAVING                                                AND (AutoFeed Catchup                                                          leaving is not blocked)                                               ST.sub.-- WAIT.sub.--                                                                   (Trailing edge at                                                                            ST.sub.-- WAIT.sub.--                                                                   count down=GwCatchupTime                       ON.sub.-- LEAVING                                                                       AutoFeed Catchup Leaving)                                                                    ON.sub.-- ACK                                                                           (isr: AF.sub.-- MOTOR.sub.-- ACCEL                                             or AF.sub.-- MOTOR.sub.-- DECEL)               __________________________________________________________________________

    __________________________________________________________________________     APPENDIX G                                                                     Present                   Next                                                 State     Inputs          State     Outputs                                    __________________________________________________________________________     READY     SST.sub.-- REV.sub.-- UP from:                                                                 REV.sub.-- UP                                                                            Start AF Catchup motor                               SupvSysState              to go to normal speed                      REV.sub.-- UP                                                                            MSG.sub.-- AF.sub.-- CATCHUP.sub.-- ACK                                                        REV.sub.-- UP                                                                            MSG.sub.-- REV.sub.-- UP.sub.-- OK;T                                           to:                                                                            SupvSysState                                         SST.sub.-- GRINDING                                                                            GRINDING                                             GRINDING  SST.sub.-- PURGING                                                                             PURGING                                                        SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                           STOPPING.sub.--                                                                          Stop AF Catchup Motor                                                ON.sub.-- JAM                                                                            MSG.sub.-- POLL to SupvAutoFeed            PURGING   (SST.sub.-- IS.sub.-- PURGED or                                                                PURGING   MSG.sub.-- PURGED.sub.-- OK;T to:                    MSG.sub.-- POLL) and      SupvSysState.                                        GpstLetter==NULL and                                                           no Mail being Singulated                                                       (SST.sub.-- IS.sub.-- PURGED or                                                                PURGING   MSG.sub.-- POLL to:                                  MSG.sub.-- POLL) and      SupvAutoFeed                                         (GpstLetter!=NULL or                                                           Mail is being singulated)                                                      SST.sub.-- STOP.sub.-- ON.sub. -- JAM                                                          STOPPING.sub.--                                                                          Stop AF Catchup Motor                                                ON.sub.-- JAM                                                                            MSG.sub.-- POLL to SupvAutoFeed                      SST.sub.-- RAMP.sub.-- DOWN                                                                    RAMP.sub.-- DOWN                                                                         Stop AF Catchup Motor                                                          MSG.sub.-- POLL to SupvAutoFeed            RAMP.sub.-- DOWN                                                                         MSG.sub.-- POLL & (AF Catchup                                                                  RAMP.sub.-- DOWN                                                                         MSG.sub.-- POLL to:                                  Motor Moving OR AF        SupvAutoFeed                                         Singulator moving)                                                             MSG.sub.-- POLL & AF Catchup                                                                   RAMP.sub.-- DOWN                                                                         MSG.sub.-- RAMP.sub.-- DOWN.sub.--                                             OK;T to:                                             Not Moving & AF           SupvSysState                                         Singulator not moving                                                          SST.sub.-- READY from:                                                                         READY                                                          SupvSysState                                                         STOPPING.sub.--                                                                          MSG.sub.-- POLL & (AF Catchup                                                                  STOPPING.sub.--                                                                          MSG.sub.-- POLL to:                        ON.sub.-- JAM                                                                            Motor Moving OR AF                                                                             ON.sub.-- JAM                                                                            SupvInserter                                         Singulator Moving)                                                             MSG.sub.-- POLL & AF Catchup                                                                   STOPPING.sub.--                                                                          MSG.sub.-- STOP.sub.-- ON.sub.--                                               JAM.sub.-- OK;T to:                                  Motor Not Moving &                                                                             ON.sub.-- JAM                                                                            SupvSysState                                         Singulator Not Moving                                                          SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                        STOPPED.sub.--                                                                 ON.sub.-- JAM                                        STOPPED.sub.--                                                                           SST.sub.-- JAM.sub.-- RECOVERY from                                                            JAM.sub.--                                                                               Start AF catchup at slow                   ON.sub.-- JAM                                                                            SupvSysState    RECOVERY  speed.                                     JAM.sub.--                                                                               (SST.sub.-- IS.sub.-- RECOVERED or                                                             JAM.sub.--                                                                               MSG.sub.-- RECOVERED.sub.-- OK;T to:       REVOVERY  MSG.sub.-- POLL) and                                                                           RECOVERY  SupvSysState.                                        GpstLetter==NULL                                                               && no mail in singulator                                                       (SST.sub.-- IS.sub.-- RECOVERED or                                                             JAM.sub.--                                                                               MSG.sub.-- POLL to:                                  MSG.sub.-- POLL) and                                                                           RECOVERY  SupvAutoFeed.                                        (GpstLetter!=NULL OR                                                           there is mail in singulator)                                                   SST.sub.-- REV.sub.-- UP from                                                                  REV.sub.-- UP                                                                            Start AF Catchup Motor                               SupvSysState              to go to normal speed.                               SST.sub.-- RAMP.sub.-- DOWN from                                                               RAMP.sub.-- DOWN                                                                         Stop AF Catchup Motor.                               SupvSysState              MSG.sub.-- POLL to SupvAutoFeed.           ESTOP.sub.--                                                                             SST.sub.-- STOPPED, SST.sub.-- READY                                                           READY                                                AFTER.sub.-- READY                                                                       SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                        STOPPED.sub.--                                                                 ON.sub.-- JAM                                        ANY STATE ESTOP           ESTOP.sub.-- AFTER.sub.--                                                      READY                                                          MSG.sub.-- INCOMMING                                                                           SAME      CALCULATE GWCATCHUPTIME                    __________________________________________________________________________

    __________________________________________________________________________     APPENDIX H                                                                     Present                Next                                                    State    Inputs        State         Outputs                                   __________________________________________________________________________     Any      SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS                                               Same          MSG.sub.-- MAIL.sub.-- IN.sub.--                                               SYS:TRUE                                           && no mail in the           to SupvSysState                                    induction line                                                                 SST.sub.-- IS.sub.-- MAIL.sub.-- IN.sub.-- SYS                                               Same          MSG.sub.-- MAIL.sub.-- IN.sub.--                                               SYS:FALSE                                          && There is mail in         to SupvSysState                                    the induction line                                                             MSG.sub.-- INCOMING from                                                                     Same          Insert into Ordered                                Manual Feed                 List of expected                                                               letters                                            SST.sub.-- IS.sub.-- RECOVERED                                                               Same          bJamRecovery = TRUE                                                            MSG.sub.-- POLL to                                                             ReadPrint                                          SST.sub.-- IS.sub.-- PURGING                                                                 Same          bPurging = TRUE                                                                MSG.sub.-- POLL to                                                             ReadPrint                                          SST.sub.-- GO.sub.-- HOME                                                                    Same          Trigger Induction                                                              belt encoder                                                                   counter to reload                                                              "zero" value.                                                                  MSG.sub.-- HOMED.sub.-- OK to                                                  SysState                                  NOTE: No mail in induction line means that the                                 induction order list is empty.                                                 ST.sub.-- STOPPED                                                                       SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                                SST.sub.-- REV.sub.-- UP                                                                     ST.sub.-- REV.sub.-- UP                                                                      Start Induction Belts                                                          MSG.sub.-- POLL to Read                                                        Print.                                    ST.sub.-- REV.sub.-- UP                                                                 MSG.sub.-- POLL &&                                                                           ST.sub.-- REV.sub.-- UP                                                                      MSG.sub.-- POLL to ReadPrint                       induction speed                                                                != Stacker speed                                                               MSG.sub.-- POLL &&                                                                           ST.sub.-- REV.sub.-- UP                                                                      MSG.sub.-- REV.sub.-- UP.sub.--                                                OK:TRUE                                            induction speed             to SysState                                        ==Stacker speed                                                                SST.sub.-- GRINDING                                                                          ST.sub.-- READING                                                SST.sub.-- RAMP.sub.-- DOWN                                                                  ST.sub.-- RAMP.sub.-- DOWN                                                                   Start to stop belts                                SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                       ST.sub.-- RAMP.sub.--                                                                   MSG.sub.-- POLL &&                                                                           ST.sub.-- RAMP.sub.-- DOWN                                                                   MSG.sub. -- POLL to ManFeed               DOWN     !bRampedDown                                                                   MSG.sub.-- POLL && Catchup                                                                   ST.sub.-- STOPPED                                                                            MSG.sub.-- RAMP.sub.-- DOWN.sub.--                                             OK:TRUE                                            bRampedDown                 to SysState                                        SST.sub.-- READY                                                                             ST.sub.-- STOPPED                                                SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED                                       ST.sub.-- READING                                                                       No Mail && bPurging                                                                          ST.sub.-- READING                                                                            MSG.sub.-- PURGED.sub.-- OK to                                                 SysState                                           SST.sub.-- REV.sub.-- UP                                                                     ST.sub.-- REV.sub.-- UP                                                                      Increase Induction                                                             belt speed.                                                                    bJamRecovery =                                                                 false                                              SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                         ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                      MSG.sub.-- POLL to Read                                                        Print, Start                                                                   stopping induction                                                             motors.                                            SST.sub.-- ESTOPPED                                                                          ST.sub.-- ESTOPPED                                      ST.sub.-- STOPPING                                                                      MSG.sub.-- POLL &&                                                                           ST.sub.-- STOPPING.sub.-- ON.sub.-- JAM                                                      MSG.sub.-- POLL to ReadPrint              .sub.-- ON.sub.-- JAM                                                                   moving                                                                         MSG.sub.-- POLL && Cleat                                                                     ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                       MSG.sub.-- STOP.sub.-- ON.sub.--                                               JAM.sub.-- OK to                                   !moving                     SysState                                           SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  ST.sub.-- STOPPED                                                                       SST.sub.-- JAM.sub.-- RECOVERY                                                               ST.sub.-- READING                                                                            Start Induction belts                     .sub.-- ON.sub.-- JAM                at jam recovery                                                                speed.                                             SST.sub.-- ESTOPPED                                                                          ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                  ST.sub.-- ESTOPPED                                                                      SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                      ST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                           SST.sub.-- READY                                                                             ST.sub.-- STOPPED                                       __________________________________________________________________________

    __________________________________________________________________________     APPENDIX I                                                                     Present               Next                                                     State    Inputs       State    Outputs                                         __________________________________________________________________________     ST.sub.-- WAIT.sub.--                                                                   leading edge at                                                                             ST.sub.-- WAIT.sub.--                                                                   GnAccelDirec, GwCatchupTime                     ON.sub.-- ENTER                                                                         Ins Catchup Enter                                                                           ON.sub.--                                                                               ON.sub.-- INSIDE                                ST.sub.-- WAIT.sub.--                                                                   (trailing edge at                                                                           ST.sub.-- WAIT.sub.--                                                                   isr: count=GwCatchupTime                        ON.sub.-- INSIDE                                                                        Ins Catchup Enter) AND                                                                      ON.sub.-- ACK                                                                           (isr: INS.sub.-- MOTOR.sub.-- ACCEL                      (Ins Catchup Leaving  or INS.sub.-- MOTOR.sub.-- DECEL)                        is blocked)                                                                    (trailing edge at                                                                           ST.sub.-- WAIT.sub.--                                             Ins Catchup Enter) AND                                                                      ON.sub.-- LEAVING                                                 (Ins Catchup Leaving is                                                        not blocked)                                                          ST.sub.-- WAIT.sub.--                                                                   trailing edge at Ins                                                                        ST.sub.-- WAIT.sub.--                                                                   count down=GwCatchupTime                        ON.sub.-- LEAVING                                                                       Catchup Leaving                                                                             ON.sub.-- ACK                                                                           (isr: INS.sub.-- MOTOR.sub.-- ACCEL                                            or INS.sub.-- MOTOR.sub.-- DECEL)               ST.sub.-- WAIT.sub.--                                                                   Motor Ack    ST.sub.-- WAIT.sub.--                                                                   MSG.sub.-- INCOMMING TO                         ON.sub.-- ACK         ON.sub.-- ENTER                                                                         SUPV.sub.-- STACKER                             __________________________________________________________________________

    __________________________________________________________________________     APPENDIX J                                                                     Present                     Next                                               State     Inputs            State     Outputs                                  __________________________________________________________________________     IDLE      SST.sub.-- GO.sub.-- HOME from:                                                                  READY     MSG.sub.-- HOME.sub.-- OK;T to:                    SupvSysState                SupvSysState                             READY     SST.sub.-- REV.sub.-- UP from:                                                                   REV.sub.-- UP                                                                            inserter INS.sub.-- MOTOR.sub.--                                               NORMAL                                             SupvSysState                                                         REV.sub.-- UP                                                                            MSG.sub.-- INS.sub.-- MOTOR.sub.-- ACK from:                                                     REV.sub.-- UP                                                                            MSG.sub.--  REV.sub.-- UP.sub.--                                               OK;T to:                                           isrInsMotorAck              SupvSysState                                       SST.sub.-- GRINDING                                                                              GRINDING                                                     SST.sub.-- RAMP.sub.-- DOWN                                                                      RAMP.sub.-- DOWN                                                                         inserter INS.sub.-- MOTOR.sub.--                                               STOP                                     GRINDING  SST.sub.-- PURGING                                                                               PURGING                                                      SST.sub.-- STOP.sub.-- ON.sub.-- JAM                                                             STOPPING.sub.--                                                                          inserter INS.sub.-- MOTOR.sub.--                                               STOP                                                                 ON.sub.-- JAM                                      PURGING   (SST.sub.-- IS.sub.-- PURGED or                                                                  PURGING   MSG.sub.-- PURGED.sub.-- OK;T to:                  MSG.sub.-- POLL) and        SupvSysState.                                      (empty queue and                                                               GnInsState = WAIT.sub.-- ON.sub.-- ENTER)                                      (SST.sub.-- IS.sub.-- PURGED or                                                                  PURGING   MSG.sub.-- POLL to:                                MSG.sub.-- POLL) and        SupvInserter                                       not empty queue                                                                SST.sub.-- RAMP.sub.-- DOWN                                                                      RAMP.sub.-- DOWN                                                                         inserter INS.sub.-- MOTOR.sub.--                                               STOP                                     RAMP.sub.-- DOWN                                                                         MSG.sub.-- INS.sub.-- MOTOR.sub.-- ACK                                                           RAMP.sub.-- DOWN                                                                         MSG.sub.-- RAMP.sub.-- DOWN.sub.--                                             OK;T to:                                                                       SupvSysState                                       SST.sub.-- READY from:                                                                           READY                                                        SupvSysState                                                         ANY STATE ESTOP             ESTOP.sub.-- AFTER.sub.--                                                      READY                                                        MSG.sub.-- INCOMMING                                                                             SAME      CALCULATE GwCATCHUPTIME                  STOPPING.sub.--                                                                          MSG.sub.-- INS.sub.-- MOTOR.sub.-- ACK                                                           STOPPING.sub.--                                                                          MSG.sub.-- STOP.sub.-- ON.sub.--                                               JAM.sub.-- OK;T to:                      ON.sub.-- JAM               ON.sub.-- JAM                                                                            SupvSysState                                       SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                          STOPPED.sub.--                                                                 ON.sub.-- JAM                                      STOPPED.sub.--                                                                           SST.sub.-- JAM.sub.-- RECOVERY from                                                              JAM.sub.--                                                                               inserter INS.sub.-- MOTOR.sub.--                                               SLOW                                     ON.sub.-- JAM                                                                            SupvSysState      RECOVERY                                           JAM.sub.--                                                                               (SST.sub.-- IS.sub.-- RECOVERED or                                                               JAM.sub.--                                                                               MSG.sub.-- RECOVERED.sub.-- OK;T                                               to:                                      RECOVERY  MSG.sub.-- POLL) and                                                                             RECOVERY  SupvSysState.                                      (empty queue and                                                               GnInsState = WAIT.sub.-- ON.sub.-- ENTER)                                      (SST.sub.-- IS.sub.-- RECOVERED or                                                               JAM.sub.--                                                                               MSG.sub.-- POLL to:                                MSG.sub.-- POLL) and                                                                             RECOVERY  SupvInserter.                                      not empty queue                                                                SST.sub.-- REV.sub.-- UP from                                                                    REV.sub.-- UP                                                                            inserter INS.sub.-- MOTOR.sub.--                                               NORMAL                                             SupvSysState                                                                   SST.sub.-- RAMP.sub.-- DOWN from                                                                 RAMP.sub.-- DOWN                                                                         inserter INS.sub.-- MOTOR.sub.--                                               STOP                                               SupvSysState                MSG.sub.-- POLL to SupvInserter          ESTOP.sub.--                                                                             SST.sub.-- IDLE   IDLE                                               AFTER.sub.-- READY                                                                       SST.sub.-- STOPPED, SST.sub.-- READY                                                             READY                                                        SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                          STOPPED.sub.--                                                                 ON.sub.-- JAM                                      __________________________________________________________________________

    __________________________________________________________________________     APPENDIX K                                                                     Present                    Next                                                State     Inputs           State     Outputs                                   __________________________________________________________________________     Any state ESTOP            ESTOP.sub.--                                                                   AFTER.sub.-- READY                                  IDLE      SST.sub.-- GO.sub.-- HOME from:                                                                 HOMING    stacker STK.sub.-- MOTOR.sub.--                                                SLOW                                                SupvSysState                                                         HOMING    MSG.sub.-- CHAIN.sub.-- HOME from:                                                              HOMING    MSG.sub.-- HOME.sub.-- OK;T to:                     isrChainHome( )            SupvSysState                                                                   stacker STK.sub.-- MOTOR.sub.--                                                STOP                                                SST.sub.-- GO.sub.-- HOME from:                                                                 HOMING    MSG.sub.-- HOME.sub.-- OK;T to:                     SupvSysState & bHome       SupvSysState                                        SST.sub.-- STOPPED from:                                                                        READY                                                         SupvSysState                                                         READY     SST.sub.-- REV.sub.-- UP from:                                                                  REV.sub.-- UP                                                                            stacker STK.sub.-- MOTOR.sub.--                                                FAST                                                SupvSysState                                                         REV.sub.-- UP                                                                            MSG.sub.-- STK.sub.-- MOTOR.sub.-- ACK                                                          REV.sub.-- UP                                                                            MSG.sub.--  REV.sub.-- UP.sub.--                                               OK;T to:                                                                       SupvSysState                                        SST.sub.-- GRINDING                                                                             GRINDING                                            GRINDING  SST.sub.-- PURGING                                                                              PURGING                                                       SST.sub.-- STOP.sub.-- ON.sub. -- JAM                                                           STOPPING.sub.--                                                                          stacker STK.sub.-- MOTOR.sub.--                                                STOP                                                                 ON.sub.-- JAM                                                                            MSG.sub.-- POLL to SupvStacker.           PURGING   (SST.sub.-- IS PURGED or                                                                        PURGING   MSG.sub.-- PURGED OK;T to:                          MSG.sub.-- POLL) and       SupvSysState.                                       GpstStackEventTop==NULL                                                        (SST.sub.-- IS.sub.-- PURGED or                                                                 PURGING   MSG.sub.-- STK.sub.-- POLL to:                      MSG.sub.-- POLL) and       SupvStacker                                         GpstStackEventTop!=NULL                                                        SST.sub.-- RAMP.sub.-- DOWN                                                                     RAMP.sub.-- DOWN                                                                         stacker STK.sub.-- MOTOR.sub.--                                                STOP                                                                           MSG.sub.-- POLL to SupvStacker.           RAMP.sub.-- DOWN                                                                         MSG.sub.-- POLL & motor moving                                                                  RAMP.sub.-- DOWN                                                                         MSG.sub.-- POLL to:                                                            SupvStacker                                         MSG.sub.-- POLL & motor not moving                                                              RAMP.sub.-- DOWN                                                                         MSG.sub.-- RAMP.sub.-- DOWN.sub.--                                             OK;T to:                                                                       SupvSysState                                        SST.sub.-- READY from:                                                                          READY                                                         SupvSysState                                                         STOPPING.sub.--                                                                          MSG.sub.-- POLL & motor moving                                                                  STOPPING.sub.--                                                                          MSG.sub.-- POLL to:                       ON.sub.-- JAM              ON.sub.-- JAM                                                                            SupvStacker                                         MSG.sub.-- POLL & motor not moving                                                              STOPPING.sub.--                                                                          MSG.sub.-- STOP.sub.-- ON.sub.--                                               JAM.sub.-- OK;T to:                                                  ON.sub.-- JAM                                                                            SupvSysState                                        SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         STOPPED.sub.--                                                                 ON.sub.-- JAM                                       STOPPED.sub.--                                                                           SST.sub.-- JAM.sub.-- RECOVERY from                                                             JAM.sub.--                                                                               stacker STK.sub.-- MOTOR.sub.--                                                SLOW                                      ON.sub.-- JAM                                                                            SupvSysState     RECOVERY                                            JAM.sub.--                                                                               (SST.sub.-- IS.sub.-- PURGED or                                                                 JAM.sub.--                                                                               MSG.sub.-- PURGED.sub.-- OK to            RECOVERY  MSG.sub.-- POLL) and                                                                            RECOVERY  SupvSysState                                        GpstStackEventTop==NULL                                                        (SST.sub.-- IS.sub.-- PURGED or                                                                 JAM.sub.--                                                                               MSG.sub.-- POLL to                                  MSG.sub.-- POLL) and                                                                            RECOVERY  SupvStacker                                         GpstStackEvenTop!=NULL                                                         SST.sub.-- REV.sub.-- UP from                                                                   REV.sub.-- UP                                                                            stacker STK.sub.-- MOTOR.sub.--                                                FAST                                                SupvSysState                                                                   SST.sub.-- RAMP.sub.-- DOWN from                                                                RAMP.sub.-- DOWN                                                                         stacker STK.sub.-- MOTOR.sub.--                                                STOP                                                SupvSysState               MSG.sub.-- POLL to SupvStacker.           STOP.sub.--                                                                              SST.sub.-- IDLE  IDLE                                                AFTER.sub.-- READY                                                                       SST.sub.-- STOPPED, SST.sub.-- READY                                                            READY                                                         SST.sub.-- STOPPED.sub.-- ON.sub.-- JAM                                                         STOPPED.sub.--                                                                 ON.sub.-- JAM                                       __________________________________________________________________________

    __________________________________________________________________________     APPENDIX L                                                                     Present                   Next                                                 State     Inputs          State     Outputs                                    __________________________________________________________________________     Any state ESTOP           ESTOP.sub.--                                                                   AFTER.sub.-- READY                                             MSG.sub.-- INCOMING                                                                            --        Put the letter at the                                                          head of the sensor line                    EADY      SST.sub.-- GRINDING                                                                            GRINDING                                             GRINDING  SST.sub.-- READY                                                                               READY                                                          MSG.sub.-- JAM from any isr.                                                                   JAM.sub.--                                                                               MSG.sub.-- JAM to: SupvSysState                                      RECOVERY  MSG.sub.-- KILL.sub.-- LETTER to:                                              Motor Supervisors                                                              MSG.sub.-- JAM to: SupvSysConsole          JAM.sub.--                                                                               SST.sub.-- GRINDING                                                                            GRINDING                                             RECOVERY  SST.sub.-- READY                                                                               READY                                                          MSG.sub.-- JAM from any isr.                                                                   JAM.sub.--                                                                               MSG.sub.-- KILL.sub.-- LETTER to:                                    RECOVERY  Motor Supervisors                          ESTOP     SST.sub.-- JAM.sub.-- RECOVERY                                                                 JAM.sub.--                                           AFTER.sub.-- READY.sub.-- RECOVERY                                                       SST.sub.-- STOPPED,SST.sub.-- READY,                                                           READY                                                          SST.sub.-- IDLE                                                      __________________________________________________________________________

    __________________________________________________________________________     APPENDIX M                                                                     __________________________________________________________________________     switch (wMsg) {                                                                case MSC.sub.-- INIT:                                                          start up the counter timer.                                                    break;                                                                         case MSC.sub.-- CARRIER.sub.-- REQUEST                                         *-          Find out which carrier is next available: The                                  wSource ID denotes who wants a carrier, (the next                              carrier is different for each of the feed                                      stations) This done by finding the carrier that                                is closest to the starting line 155                                wNextCarrier = GetNexCarrier (wSourceID) ;                                     *-          BEGIN CRITICAL SECTION: Disable all interrupts -*                  *-          check to see whether it is too close.                                          IF ((absolute position now - next carrier time) <                              MAX.sub.-- SCHEDULE.sub.-- TIME) THEN                                             get the next carrier                                                        END                                                                DO                                                                                         IF (carrier is taken) THEN                                                        increment the carrier list index                                            END                                                                WHILE carrier is taken                                                                     GnFeedNext = carrier number!!!                                                  carrier list [this carrier] is taken, this letter;                            *- END CRITICAL SECTION Enable Interrupts-*                                    *- send a message to the wSourceID MSG.sub.-- INCOMMING            break; *- MSG.sub.-- CARRIER.sub. -- REQUEST -*                                __________________________________________________________________________ 

What is claimed is:
 1. A method of processing pieces of internal mail received from an internal source in a system including a stacker module having a number of carriers and bins, a plurality of serially connected induction transfer modules, including a feeder module, that are positioned to transport the pieces of internal mail from the feeder module to the stacker module, the method comprising the steps of:(a) monitoring the position of each carrier; (b) pre-selecting an empty carrier; (c) feeding a piece of internal mail from the feeder module to another induction transfer module at a desired time based on the position of the pre-selected carrier; (d) tracking the position of the piece of internal mail through the induction transfer modules; (e) obtaining address information from the piece of internal mail, wherein said address information includes a mail stop; (f) selecting a bin for the piece of internal mail based on said address information, the selected bin corresponding to a mail stop; (g) transferring the piece of internal mail from a last induction transfer module to the pre-selected carrier; (h) diverting the piece of internal mail from the pre-selected carrier to the selected bin; (i) monitoring the thickness of each piece of internal mail diverted to the selected bin; and (j) determining when the selected bin needs to be replaced based on the monitoring of the thickness.
 2. A method according to claim 1, further comprising the step of:adjusting the position of piece of internal mail within an induction transfer module based on the position of the selected carrier.
 3. A method according to claim 2, wherein the system further includes a series of sensor pairs located amongst the plurality of induction transfer modules, and said method further comprises the steps of:monitoring the piece of internal mail arriving at and leaving each of the sensor pairs; and detecting a position error in response to another piece of internal mail arriving at a sensor pair before the piece of internal mail leaves the sensor pair.
 4. A method according to claim 1, wherein said address information further includes an addressee's name.
 5. A method according to claim 1, wherein at least some of the pieces of internal mail are interoffice mail envelopes including a region in which an addressee's name may be written and a region in which a mail stop associated with the addressee's name may be written.
 6. A method according to claim 5, wherein said region in which an addressee's name may be written includes a plurality of boxes in which single characters of the addressee's name may be written.
 7. A method according to claim 5, wherein said region in which a mail stop may be written includes a plurality of boxes in which single characters of the mail stop may be written.
 8. A method of processing pieces of incoming mail received from an external source in a system including a stacker module having a number of carriers and bins, a plurality of serially connected induction transfer modules, including a feeder module, that are positioned to transport the pieces of incoming mail from the feeder module to the stacker module, the method comprising the steps of:(a) monitoring the position of each carrier; (b) pre-selecting an empty carrier; (c) feeding a piece of incoming mail from the feeder module to another induction transfer module at a desired time based on the position of the pre-selected carrier; (d) tracking the position of the piece of incoming mail through the induction transfer modules; (e) obtaining address information from the piece of incoming mail, wherein said address information includes an addressee's name; (f) selecting a bin for the piece of incoming mail based on said address information, the selected bin corresponding to a mail stop; (g) transferring the piece of mail from a last induction transfer module to the pre-selected carrier; and (h) diverting the piece of incoming mail from the pre-selected carrier to the selected bin.
 9. A method according to claim 8, further including the steps of:monitoring the thickness of each piece of incoming mail diverted to the selected bin; and determining when the selected bin needs to be replaced based on the monitoring of the thickness.
 10. A method according to claim 8, further comprising the step of:adjusting the position of piece of incoming mail within an induction transfer module based on the position of the selected carrier.
 11. A method according to claim 10, wherein the system further includes a series of sensor pairs located amongst the plurality of induction transfer modules, and said method further comprises the steps of:monitoring the piece of incoming mail arriving at and leaving each of the sensor pairs; and detecting a position error in response to another piece of incoming mail arriving at a sensor pair before the piece of incoming mail leaves the sensor pair.
 12. A method according to claim 8, wherein said address information further includes a mail stop.
 13. A modular mail processing control system for controlling the flow of mail through a series of induction transfer modules to a stacker/transport module that includes a number of carriers and bins, said system comprising:feeder means, located in one of the induction transfer modules, for injecting a piece of mail into another induction transfer module at a desired time based on a pre-selected carrier being at a given position, and for identifying the piece of mail; encoder means, located in one of the induction transfer modules, for obtaining address information from the piece of mail and for identifying a bin for the piece of mail, wherein said address information includes a mail stop, and the bins correspond to mail stops; tracking means, located in each of the induction transfer modules, for tracking the position of the piece of mail as it moves through the induction transfer modules, and in response to a position error stopping the series of induction transfer modules, storing the identification of at least the piece of mail involved in the position error and storing the position of the induction transfer modules and the stacker/transport module; inserter means, located in one of the induction transfer modules for inserting the piece of mail into the pre-selected carrier when the pre-selected carrier arrives at a desired location; and means for diverting the piece of mail from the carrier to the identified bin.
 14. A modular mail processing control system according to claim 13, wherein the tracking means includes:a series of sensor pairs located amongst the induction transfer modules for sensing the presence of the pieces of mail; means for identifying the piece of mail arriving at and leaving each of the sensor pairs; and means for detecting a position error in response to another piece of mail arriving at a sensor pair before the piece of mail leaves the sensor pair.
 15. A modular mail processing control system according to claim 13, wherein the encoder means includes:an optical character reader; means for identifying the bin in accordance with a predetermined sort plan; and means for verifying the obtained address information.
 16. A modular mail processing control system according to claim 13, further comprising:means for storing a plurality of sort plans; means for selecting a sort plan; and wherein the encoder means includes: an optical character reader; means for identifying the bin in accordance with said selected sort plan; and means for verifying said obtained address information.
 17. A modular mail processing control system according to claim 16, wherein said address information further includes an addressee's name, and wherein said means for verifying said obtained address information verifies that the obtained address is correct based upon a correlation of the addressee's name with the mail stop of the obtained address.
 18. A modular mail processing control system according to claim 13, wherein at least some of the pieces of mail are pieces of internal mail received from an internal source.
 19. A modular mail processing control system according to claim 13, wherein at least some of the pieces of mail are pieces of incoming mail received from an external source.
 20. A modular mail processing control system according to claim 13, wherein at least some of said pieces of internal mail are interoffice mail envelopes including a region in which an addressee's name may be written and a region in which a mail stop associated with the addressee's name may be written.
 21. A modular mail processing control system according to claim 20, wherein said region in which an addressee's name may be written includes a plurality of boxes in which single characters of the addressee's name may be written.
 22. A modular mail processing control system according to claim 20, wherein said region in which a mail stop may be written includes a plurality of boxes in which single characters of the mail stop may be written. 